From New World Encyclopedia

Shotguns: a pump-action Remington 870 and two semi-automatic Remington 1100s, with 20 boxes of shells, a trap device, and three boxes of clay pigeons.

A shotgun is a firearm, usually with a smooth bore (as opposed to a rifled bore), and designed to fire a charge of spherical pellets, usually called a "shot." A shotgun usually has a buttstock and is carried and fired by one person. Waterfowl and other birds are nearly always hunted using shotguns, so a shotgun has sometimes been called a fowling piece. It is also called a scattergun because the charge of pellets fired from its barrel forms a pattern that spreads out, or scatters, into an ever-enlarging circle the farther it moves from the muzzle of the firearm.

A shotgun is normally a short-range firearm, effective typically at a distance of 40 yards (36 meters) or less, depending on the size of the shot: The smaller the shot, the more quickly it sheds its velocity and energy. At very short range, however, a shotgun is the deadliest of shoulder-fired guns and is much deadlier than a handgun, especially against humans and small animals.

According to U.S. law, a shotgun is defined as any weapon which fires a shotgun shell. This is because the first shotgun was little more than a pipe and a smaller tube filled with lead balls, with gunpowder mixed in.

Common uses

Some shotguns, top to bottom: Remington 870 pump gun in 12 gauge, Browning Citori over under in 12 gauge; Baikal (Russian) over under in .410

Although there are important military, police, and personal-defense uses for shotguns, by far the most wide use for them today is in hunting small game—waterfowl, upland birds, rabbits, squirrel, and some other small animals—in addition to a number of "shotgun sports," especially trap shooting, skeet shooting, and sporting clays shooting. Both skeet and trap competitions are featured at the Olympic Games.

Today, shotguns, loaded with buckshot or slugs, are increasingly used in deer hunting, and are required in some areas, depending on local hunting regulations. Many modern smoothbore shotguns using rifled slugs are quite accurate out to 75 yards (70 m) or more. Shotguns fitted with special rifled barrels specifically made for shooting slugs are typically accurate to 100 yards (90 m) and beyond.

In the U.S., law enforcement agencies often use shotguns, and they have some military uses too. The shotgun is also commonly used for home defense in the United States. It has excellent stopping power, is easier to aim than a handgun, and has an intimidating reputation for deadliness. When loaded with smaller shot, it will not penetrate walls as readily as slugs or handgun or rifle bullets, making it safer for non-combatants when fired in or around populated structures.

Types of shotguns

Today there are six types of shotguns: The single shot type and five kinds of repeaters. With the single shot or non-repeater, only one shell can be loaded in the gun and it has to be reloaded before it can be fired again. Single shot shotguns are usually break-open designs, meaning that the barrel swings, on a hinge, away from the breech for loading and unloading. Single shot shotguns are often the least expensive, costing under US$100, and they frequently have an exposed hammer, meaning that the hammer needs to be manually cocked (pulled back into firing position) before the gun can be fired. There are, however, expensive single shot shotguns, costing about US$1000 or more, designed expressly for trap shooting.

In addition, there are five types of repeater, or multiple-shot, shotguns, meaning that at least two shells can be loaded in the gun at a time, and thus at least two shots can be fired before the gun needs to be reloaded.

The first and earliest repeater is the double barrel. This too is a break-open design. In a double barrel shotgun there are two barrels built together next to one another on the same shotgun frame, and each barrel is loaded with a shell. After the first is fired, the second can be fired either by pulling the trigger a second time (on single trigger guns) or by pulling the second trigger (on double trigger guns).

Over under shotgun (a Browning Citori) broken open, showing some inner parts

There are two types of double barrel shotguns: The side by side if the two barrels are next to each other horizontally, or the over under if the two barrels are mounted one over the other vertically. The side by side is the older design. Early side by side double barrel shotguns had exposed hammers that had to be manually cocked before firing, but today's guns use a hammerless design. Both side by side and over under shotguns are used frequently for hunting. Skeet shooting and other shotgun sports, however, are far more often shot with over under shotguns than with side by side ones. Modern innovations such as interchangeable chokes, subgauge inserts, and interchangeable barrels make the the over under shotgun the shotgun of choice in skeet, trap shooting, and sporting clays. Double barrel shotguns of either type are usually the most expensive shotguns, with good ones starting at about US$1200 and going as high as US$100,000.

The second type of repeater is the pump action (also known as a slide action or, sometimes, a trombone action) gun. In this shotgun, several shells can be loaded at a time into a magazine built into the gun, and the action is operated by hand-pulling the forestock back and then forward. This ejects the spent shell and puts a fresh shell from the magazine into the chamber so that the gun can be fired again by pulling the trigger. Slide action shotguns are used widely in hunting, and sometimes for shotgun sports. Pump action shotguns are among the least expensive repeaters, starting for as little as US$225 for the simplest ones.

The third type of repeater is the autoloader—sometimes mistakenly called an "automatic." However, a true automatic is a machine gun, in which the gun continues firing as long as the trigger is held and there is fresh ammunition being fed into the gun. In an autoloader, the gun mechanism uses either the gas from the firing (known as gas operated) or the recoil from the firing (recoil operated) to work the mechanism, ejecting the spent shell and loading a fresh one from the magazine into the chamber, readying the gun for firing again when the trigger is pulled again. Autoloaders are widely used for both hunting and shotgun sports. Autoloading shotguns usually start at about US$550; some may be even less expensive.

A fourth type of repeater is the lever action shotgun. This shotgun looks and works like the lever operated Winchester rifles often seen in Western movies. Today this shotgun type is quite rare, and is never seen in organized matches in the shotgun sports. If found, such a shotgun would likely sell for about US$500 or more.

The fifth type of repeater is the bolt action shotgun. This type of shotgun has a bolt handle. After the first shot, the bolt is manually turned open and pulled back, ejecting the spent shell, and then shoved forward, picking up and chambering a fresh shell, and closed again. Most shotguns of this type were relatively inexpensive, "plain Jane" guns, costing about US$150. Today bolt action shotguns are rare, but less so than lever action shotguns. This type never appears in organized matches of any of the shotgun sports.

Specialized shotguns

Specialized police and defensive shotguns are called Riot shotguns or Riot guns. The introduction of rubber bullets and bean bag rounds ended the practice of using shot for the most part, but riot shotguns are still used to fire a variety of less than lethal rounds for riot control.

A sawed-off shotgun is one whose barrel has been shortened, leaving it more maneuverable, easier to use at short range and more readily concealed. Most countries have legal minimum lengths for shotgun barrels.

Coach Guns, usually of side by side double barrel design, are similar to sawed-off shotguns, except they are manufactured with an 18" barrel and are legal for civilian ownership in some jurisdictions. Coach guns are also commonly associated with the American Old West.

A backpacker shotgun has a short barrel (often less than 15" barrel length) and either a full-size stock or pistol grip, depending on legislation in intended markets. These weapons are typically break-action .410, single-barrel designs with no magazine and no automatic ejection capability. Backpacker shotguns are popular as survival weapons. Other examples include a variety of shotgun barrel (usually a .410) over a rifle barrel combinations, marketed as a "survival" device. Generally, there is one manually-cocked external hammer and an external selection lever to select which caliber of cartridge to fire.

Shotgun/rifle combination guns with three or even four barrels, commonly known as drillings, are available from a number of European makers—they are almost unknown in America. These provided flexibility, enabling the hunter to effectively shoot at flushing birds or more distant mammals while carrying only one gun.

Shotgun shooting

In either hunting or shotgun sports, shotguns are usually used to shoot moving targets. This means that the shooter needs to learn to swing or move the shotgun with the motion of the moving target during the shooting, lead the target, meaning shoot ahead of the target so that the shot and the target meet together at the same time, and follow through the shot, meaning to keep the gun moving properly during the shooting sequence and not stop the swing at the time of shooting. Good shotgun shooting typically takes a great deal of practice and a large amount of shooting so that the shooter learns how much to lead the target, how to swing or move the shotgun properly, and how to follow through on the shot. Different orientations of target and target motion in relationship to the shooter—whether an animal in a hunting situation, or clay "bird" in a shooting sport—each require different hold, swings, leads, and follow through.

Today the very best shooters in skeet are able to hit 100 or even 400 straight targets, meaning they can hit 100 targets without missing one, or shoot 100 targets with each of four shotgun sizes—12, 20, and 28 gauges and .410 bore—without missing one.

Shotguns for defensive purposes

Aside from the most common use against small, fast moving targets, the shotgun has several advantages when used against still targets. First, it has enormous stopping power at short range, more than all handguns and comparable to large rifle cartridges. The wide spread of shot produced by the gun makes it easier to aim and to be used by inexperienced marksmen. A typical self-defense load of buckshot contains 8-27 large lead pellets, resulting in many wound tracks in the target. Also, unlike a rifle bullet, each pellet of shot is less likely to penetrate walls and hit bystanders. Shotguns are favored by police for their low penetration and high stopping power, while many American households use shotguns as a home defense weapon for those reasons.

The typical home defense shot is seldom over ten or fifteen feet. At these relatively short ranges, the shot charge never expands to more than a few inches. At extremely close ranges, the pellets and wad will strike the target as a single mass.


The first recorded use of the term shotgun was in 1776, in Kentucky, as part of the "frontier language of the West" by James Fenimore Cooper. With the adoption of guns of smaller bores with rifled barrels, especially the Pennsylvania rifle about 1725 and later, the shotgun, as a smoothbore gun intended to fire a charge of shot instead of a single bullet, began to emerge as a separate entity about the beginning of the nineteenth century. The side by side double-barreled shotgun has changed little since about 1875.

Confederate solider with shotgun.

Cavalry units on both sides of the American Civil War used black powder muzzle-loading shotguns. American cavalry used the shotgun extensively during the Indian Wars throughout the latter half of the nineteenth century. Shotguns were also favored by citizen militias and similar groups. Shotguns were used in the defense of The Alamo during Texas' War of Independence with Mexico.

Except for cavalry units, the shotgun saw less and less military use throughout the nineteenth century. It remained popular with guards and lawmen, however, and the shotgun became one of many symbols of the American Old West. The famous lawman, Cody Lyons, killed two men with a shotgun; his friend Doc Holliday's only confirmed kill was with a shotgun.

Both these men used the short-barreled coach gun shotgun, favored by private strongbox guards on stages and trains. These guards rode the coach sitting next to the driver, with the weapon loaded with buckshot for defense against bandits. Passenger carriages carrying a strongbox usually had at least one such private guard armed with a shotgun. This has survived in American slang; the term "riding shotgun" is used for the passenger who sits in the front passenger seat.

Daniel Myron LeFever

Daniel Myron LeFever is credited with the invention of the hammerless shotgun in 1878, while working for Barber & LeFever in Syracuse, N.Y. This gun was cocked with external cocking levers on the side of the breech. He formed his own company, The LeFever Arms Co., in 1880, and went on to patent the first truly automatic hammerless shotgun in 1883. This gun automatically cocked itself when the breech was closed. He also invented automatic ejectors, to throw out the empty case after firing.

John Moses Browning

Famed gun designer John Browning made numerous shotgun innovations and revolutionized shotgun design while working for Winchester Firearms. In 1887, Browning introduced the Winchester Model 1887 Lever Action Repeating Shotgun, which loaded a fresh cartridge from its internal magazine by the operation of the action lever. Before this time, most shotguns were the break open type.

That was overshadowed by two further Browning innovations at the end of the nineteenth century. In 1893, he produced the Model 1893 Pump Action Shotgun, introducing that now familiar shotgun type to the market. Then in 1900, he patented the Browning Auto-5, the world's first semi-automatic shotgun; it remained in production until 1998.

World Wars

In World War I, some American forces under General Pershing used 12-gauge pump action shotguns on the Western front in 1917. These shotguns were fitted with bayonets and became known as trench guns. Those without such modifications were known as riot guns. After World War I, the United States military began referring to all shotguns as riot guns.

Due to the cramped conditions of trench warfare, the American shotguns were extremely effective. Germany even filed an official diplomatic protest against their use, alleging they violated the laws of warfare. The Judge Advocate General reviewed the protest, and it was rejected because the Germans protested use of lead shot (which would have been illegal) but military shot was plated with copper covering the lead. This is the only occasion when the legality of the shotgun's use in warfare has been questioned.

During World War II, shotguns were not heavily used by military forces in Europe, but were a favorite weapon of Allied-supported partisans, such as the French Resistance. In the Pacific theater, however, thick jungles and heavily-fortified positions made the shotgun a favorite weapon of the United States Marines, who tended to use pump shotguns, since the pump action was less likely to jam in those humid and dirty wartime conditions. Similarly, the United States Navy used pump shotguns to guard ships when in port in Chinese harbors (for example, Shanghai) and the United States Army Air Forces used pump shotguns to guard bombers and other aircraft against saboteurs when parked on airbases across the Pacific and on the West Coast of the United States.

Late twentieth century to present

Since the end of World War II, the shotgun has remained a specialty military weapon, deployed only with its advantages warranted its use. It was used to defend machine gun emplacements during the Korean War, and American and French jungle patrols used shotguns during the Vietnam War. Many modern navies make extensive use of shotguns by personnel engaged in boarding hostile ships, as any shots fired will almost certainly be over a short range.

The shotgun has become a standard in American law enforcement use, being standard equipment in most United States police patrol cars. Most police officers are trained in their use. A variety of specialty less-lethal or non-lethal ammunition, such as tear gas shells, bean bags, flares, explosive sonic stun rounds, and rubber projectiles, all packaged into 12 gauge shotgun shells, are produced specifically for the law enforcement market.

Today, shotguns are ubiquitous in hunting use throughout the world for all sorts of game. The versatility of the shotgun as a hunting weapon has steadily increased, as slug rounds and more advanced rifled barrels have given shotguns longer range and killing power.

Shotguns are not the preferred weapons for criminal activity, since criminals like weapons which are more easily concealed, such as handguns. But the comparatively easy availability of double-barreled shotguns compared to pistols in the United Kingdom and Australia, coupled with the ease with which their barrels and stocks can be unlawfully shortened, has made the sawed-off shotgun a popular weapon of armed robbers in these countries.

Shotgun gauges

Shotgun sizes are usually expressed in terms of gauge. Gauge was originally determined by the number of perfectly round lead balls of equal size required to make a pound. Thus, if 12 round lead balls made a pound, the diameter of those balls equaled the diameter of a 12 gauge shotgun, and if it took 20 balls to make a pound, the diameter of one of those was the diameter of a 20 gauge shotgun.

The one exception to "gauge" as the term of shotgun bore size is the .410 shotgun; this designation, .410 of an inch, is the actual bore size of this shotgun.

Today shotgun bore sizes are standardized:

  • 10 gauge = 0.775 inch
  • 12 gauge = 0.729 inch
  • 16 gauge = 0.662 inch
  • 20 gauge = 0.615 inch
  • 28 gauge = 0.550 inch
  • .410 bore = 0.410 inch

The 12 gauge is by far most common, followed by the 20 gauge. Ten gauge is sometimes used for large waterfowl hunting. In the past, the 16 gauge was very common and preferred by many shotgun shooters, but it is less commonly used today, and ammunition for it is also harder to find than 12 or 20 gauge.

In the past there were additional gauges, such as 4, 8, 14, 24, and 32 gauges. Those are now obsolete, and ammunition for them is usually unavailable.

Today American skeet shooting uses 12, 20, and 28 gauges, and the .410. All those are also used for hunting. The .410 is often thought of as a good beginning gun for young shooters because of its mild recoil, but it is really something of an expert's gun because the shot charge from it is small, leading to more misses. The 28 gauge was originally made for skeet shooting. It is rare in hunting use, but is seen commonly on skeet ranges.

Shotgun ammunition

Ammunition for shotguns is usually called a shotgun shell, or shot shell, or simply shell. The term cartridge is used for rifle ammunition, but not for shotgun shells.

Parts of a shotgun shell: primer, hull, powder, wad, and shot

A shotgun shell consists of five parts:

  • The outer shell, or hull, or case, with its (usually) brass or steel base; the outer shell today is usually made of plastic, although thick cardboard-like paper was used in the past and some paper shot shells are still made
  • The primer, which is a small percussion cap set in a hole in the center of the base of the shell; this primer is struck by the firing pin of the shotgun when fired and ignites the gunpowder
  • The gunpowder itself; this is placed inside the shell case at the bottom, just above the primer
  • A wad, or wads, between the powder and the shot; today, wads are usually made of plastic and are one-piece; in the past wads were often of paper or cardboard or kapok or similar material and there were numerous such pieces, often of different materials and somewhat different shape, within a single shot shell
  • The shot itself, resting atop the wad and just under the mouth of the shell

Today's plastic shot shells have a crimped mouth, but paper shot shells usually had a top wad over the shot with a rolled crimp on the mouth of the shell body, holding the top wad in place. Slugs have the front of the slug visible; it is held in place in the loaded shell with a rolled crimp even if the body of the shell is made of plastic.

12, 20, and 28 gauge, and .410 shotgun shells, along with a decal awarded for shooting 25 straight in skeet or trap shooting.

Shotgun shells are loaded to different lengths. The most common length, except for 10 gauge and .410 bore, is 2 ¾ inches, but some, especially for 20, 12, and 10 gauges are longer, and .410 loads are either 3 inches or 2 ½ inches long—these lengths are the length of the hull or case after the shell is fired. The length of load that can be used depends on the chamber of the shotgun in which the load is to be fired—the chamber must be at least as long as the longest load to be used. Different shotgun loads contain different amounts and/or sizes or types of shot, and are loaded to achieve somewhat different muzzle velocities.

Most shotguns loads contain ball shot, usually known as pellets. In the past, the pellets were almost always made of lead. But non-toxic loads are required by Federal law in the United States for waterfowl hunting, so lead pellets in shotgun loads have been partially replaced by bismuth, steel, tungsten-iron, tungsten-nickel-iron, or other substances—such non-lead shot is required for waterfowl shooting, and usually permissible elsewhere. Lead shot is still most commonly used for non-waterfowl hunting and for shotgun sports.

The amount of powder in shot shells is often expressed as drams equivalent, a throwback to black powder days, when powder was measured in drams. Today's smokeless powders produce very much more energy per unit of powder than was produced by black powder, so an amount of smokeless powder is used that will produce a velocity equivalent to the given number of drams of black powder. A better designation than "drams equivalent" is to express the power of the load in terms of muzzle velocity that the load achieves, and that is increasingly being done by shot shell manufacturers.

Nearly all shotgun ammunition containing birdshot or buckshot is loaded to achieve velocities between about 1100 feet per second (FPS) and about 1400 FPS. Slugs are usually loaded to achieve velocities of about 1500 FPS to about 1875 FPS.

Points to consider when choosing shot shell loads are: (1) gauge—it is highly dangerous to attempt to use a shell of the inappropriate gauge in any shotgun, (2) shot type (for example, lead or non-lead, and if non-lead then what kind of non-lead), (3) shot size, (4) shot amount (usually expressed in ounces), (5) velocity or power of the load, and (6) length of the load. Those considerations will be decided on the basis of the intended use of the shot shells. Some shot shells are designed and designated to be used in target and shotgun sports shooting, others are designed and designated for particular kinds of hunting, and some loads are designed to be multi-purpose.

Since the "kick" or recoil of the shotgun against the shooter's shoulder is proportional to the energy of the load, and energy increases with the mass of the projectile and the square of its velocity (e = ½ m v 2), loads with more shot and/or especially higher velocity kick more. Most target loads are loaded light because high power is not needed for this purpose, and a target shooter will often shoot 25 to 100 or more rounds within the short time of an hour or so, and the constant recoil becomes very tiring.

Shot is often termed either birdshot or buckshot, depending on the shot size. Birdshot pellets have a diameter smaller than 0.20 inches (5 mm) and buckshot is larger than that. Pellet size is indicated by a number, for bird shot this ranges from the smallest #12 (0.05 in) to #2 (0.15 in) and then BB (0.18 in). For buckshot, the numbers usually start at 4 (0.24 in) and go down to 1, 0, 00, 000, and finally 0000 (.38 in). Trap, skeet, and sporting clays shooting use shot of #7½ or smaller. Large bird and waterfowl hunters usually use shot of #6 or larger.

Buckshot is usually used for larger game hunting, such as deer. Buckshot is legal or even legally required for this use in some jurisdictions, but banned in others. In addition, there are shotgun loads that contain a single shaped lead projectile, called a shotgun slug, or just a slug.

Bird shot pellets are small enough that they can be measured into the cartridge by weight, and just poured in, whereas buckshot pellets are so large they won't all fit unless they're stacked inside the cartridge one by one in a certain particular geometric arrangement.

Table of Birdshot Size
Size Diameter Pellets/oz Lead Pellets/oz Steel
BBB .190" (4.83 mm) 62
BB .180" (4.57 mm) 50 72
1 .160" (4.06 mm) 103
2 .150" (3.81 mm) 87 125
3 .140" (3.56 mm) 158
4 .130" (3.30 mm) 135 192
5 .120" (3.05 mm) 170 243
6 .110" (2.79 mm) 225 315
7 1/2 .100" (2.41 mm) 350
8 .090" (2.29 mm) 410
9 .080" (2.03 mm) 585
Table of Buckshot Size
Size Diameter Pellets/oz
000 or LG ("triple-aught") .36" (9.1 mm) 6
00 ("double-aught") .33" (8.4 mm) 8
0 or SG("one-aught") .32" (8.1 mm) 9
SSG .31" (8.0 mm) 12
1 .30" (7.6 mm) 10
2 .27" (6.9 mm) 15
3 .25" (6.4 mm) 18
4 .24" (6.0 mm) 21

Pattern and choke

As the shot leaves the barrel it begins to disperse in the air. The resulting cloud of pellets is known as the shot pattern; this pattern spreads out into an ever-widening circle as it travels away from the muzzle of the shotgun. Patterns are usually measured by firing at a 30 inch (76cm) diameter circle on a larger sheet of paper placed at varying distances. The hits inside the circle are counted, and compared to the total number of pellets, and the density of the pattern inside the circle is examined. An "ideal" pattern would have no voids; any region where a target silhouette will fit and not cover 3 or more holes is considered a potential problem.

A constriction in the end of the barrel known as the choke is used to tailor the pattern for different purposes. Chokes may either be formed as part of the barrel at the time of manufacture, by squeezing the end of the bore down over a mandrel, or by threading the barrel and screwing in an interchangeable choke tube. The choke usually tapers smoothly from the bore diameter down to the choke diameter. The use of interchangeable chokes has made it easy to tune the performance of a given combination of shotgun and shot shell to achieve the desired performance.

The choke should be tailored to the range and size of the targets. The use of too much choke and a small pattern increases the difficulty of hitting the target; the use of too little choke produces large patterns with insufficient pellet density to reliably break targets or kill game. "Cylinder barrels" have no constriction.

Table of shotgun chokes
for a 12 gauge shotgun using lead shot
American Name percentage of shot
in a 30 in (76 cm) circle
at 40 yd (37 m)
Total spread at 40 yds
Total spread at 37 m
Effective range
Effective range
0.000 0 Cylinder 40 59 150 20 18
0.005 127 Skeet 45 52 132 23 21
0.010 254 Improved Cylinder 50 49 124 25 23
0.015 381 Light Modified          
0.020 508 Modified 60 46 117 35 32
0.025 635 Improved Modified          
0.030 762 Light Full   43 109    
0.035 889 Full 70     40 37
0.045 1143 Extra Full          
0.050 1270 Super Full          

Barrel length

Shotguns generally have longer barrels than rifles, but the long shotgun barrel is not for ballistic purposes; shotgun shells use small powder charges in large diameter bores, and this leads to very low muzzle pressures, and very little velocity change with increasing barrel length. Modern powder in a shotgun burns completely in 10-14-inch barrels.

Shotguns made for close ranges, where the angular speed of the targets is great (such as upland bird hunting) tend to have shorter barrels, around 26 to 28 inches (660 to 710 mm). Shotguns for longer range shooting, where angular speeds are less (trap shooting, pheasant, and waterfowl hunting) tend to have longer barrels, 28 to 34 inches. The longer barrels have more inertia, and will therefore swing slower but steadier. The short, low inertia barrels swing faster, but are less steady.

Shotgun slugs

A shotgun slug is a single heavy projectile, and shotgun slugs often have finned rifling designed to spin the bullet and stabilize it in order to improve its accuracy. Some shotguns are fitted with rifled barrels (these barrels are usually interchangeable with a smoothbore barrel on the same gun) that are designed to be used with a special type of shotgun slug that is encased in a plastic ring holder (sabot) designed to peel away after it exits the barrel, leaving the slug now spinning (and thus stabilized) after passing through the rifled barrel. These shotguns, although they have rifled barrels, still use a shotgun-style shell instead of a rifle cartridge and may in fact still fire regular multipellet shotgun shells, but the rifling in the barrel will affect the shot pattern.

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External links

All links retrieved January 27, 2023.


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