William Squires is an American track and field coach.
 He is well known for coaching the Greater Boston Track Club at the height of its marathon success, including marathoner Bill Rodgers, Alberto Salazar, Dick Beardsley and Greg Meyer.
Dick Beardsley (born March 21, 1956) is an American long-distance runner best known for tying for first place with Inge Simonsen in the inaugural 1981 London Marathon and his close finish with Alberto Salazar in the 1982 Boston Marathon.
Duel in the Sun: Alberto Salazar, Dick Beardsley, and America's Greatest Marathon is a 2006 book by freelance sportswriter John Brant.
 Expanded from an article featured in "Runner's World" magazine, the book tells the story of two American distance runners, Dick Beardsley and Alberto Salazar, and how their lives changed after both men ran the 1982 Boston Marathon.
 Brant, a regular contributor to "Runner's World" since 1985 and a contributing editor at "Outside", uses a writing style in the book that relies heavily on flashbacks and foreshadowing.
 The result of this style is that the story of the marathon and the story of the two men's lives are told simultaneously throughout the book.
Rodolfo Gómez Orozco (born 30 October 1950 in Mexico City) is a retired long-distance runner, who was one of the leading runners represented from Mexico in the 1970s and 1980s.
 He won the Tokyo Marathon (1981), the IAAF Citizen Golden Marathon in Athens (1982), the Rotterdam Marathon (1982), the Nike OTC Marathon (1982), the Pittsburgh Marathon (1984) and the Mexico City Marathon (1987).
 He gained prominence on American television in 1982 when he set his Personal Record of 2:09:33 while being the primary foil to Alberto Salazar's third victory in a row at the New York Marathon.
Bob Larsen (born c. 1939) is a Hall of Fame Track and field athletics coach, known largely for coaching distance runners, though he has had success coaching across a full range of events.
 Larsen is currently a coach at the Mammoth Lakes Mammoth Track Club high altitude training camp.
 His most notable athlete is Mebrahtom Keflezighi, the 2004 Olympic Silver medalist in the Marathon, an accomplishment that ended a 20-year drought in United States distance running medals at the Olympic level (28 years for male athletes).
 Building on that success, Keflezighi won the men's division of the 2009 New York Marathon, the first American athlete to accomplish that feat since Alberto Salazar did it 27 years before in 1982, and the 2014 Boston Marathon.
 Previous to that Larsen coached the UCLA Cross Country and then Track teams between 1979 and his retirement in 1999.
Galen Rupp (born May 8, 1986) is an American long-distance runner.
 He competed in the Summer Olympics in 2008 in Beijing, 2012 in London, and 2016 in Rio de Janeiro.
 In London he won the silver medal in the men's 10,000 meters, and in Rio de Janeiro he won the bronze medal in the men's marathon.
 Rupp previously competed for the University of Oregon and currently trains under Alberto Salazar as a member of the Nike Oregon Project.
Shannon Rowbury (born September 19, 1984) is an American middle-distance runner from San Francisco, California.
 She represented the United States at the 2008, 2012, and 2016 Summer Olympics.
 She also represented the United States at the World Championships in 2009, 2011, and 2013 winning the bronze medal in the 1500 meters in 2009.
 On May 2, 2015 at the IAAF World Relays Rowbury was a member of the distance medley relay team that broke the world record.
 Pending ratification in December, Rowbury is the current American record holder in the 1500 meters, breaking Mary Slaney's 32-year record on July 17, 2015, with a time of 3:56.29.
 Rowbury competed for Duke University and currently trains under Alberto Salazar as a member of the Nike Oregon Project.
Alan Culpepper (born September 15, 1972) is an American distance runner and two time United States Olympian (2000 & 2004).
 Along with competing on four World Championship teams, his accomplishments include finishing fourth in the Boston Marathon in 2005, winning the 2004 U.S. Olympic Trials Marathon and finishing 12th at the 2004 Olympic marathon in Athens.
 His 2:09:41 at the 2002 Chicago Marathon tied him with Alberto Salazar for the fastest ever debut marathon by an American, and remains his fastest marathon.
 Culpepper has won three U.S. Cross Country titles and three track titles (two at 10,000 m and one at 5,000 m).
 His personal bests include 3:55.1 for the Mile, 13:25 for 5k and 27:33 in the 10K.
Alberto Salazar (born August 7, 1958) is an American track coach and former world-class long-distance runner.
 Born in Cuba, Salazar immigrated to the United States as a child with his family.
 They moved to Manchester, Connecticut and then to Wayland, Massachusetts, where Salazar competed in track and field in high school.
 Salazar is best known for his performances in the New York City Marathon in the early 1980s and his 1982 Boston Marathon victory known as the "Duel in the Sun."
 He held American track records of 13:11.93 for 5,000 m (July 6, 1982 – Stockholm) and 27:25.61 for 10,000 m – (June 26, 1982 – Oslo).
Mario Alberto Salazar Madera (born 14 August 1975) is a Mexican politician from the National Action Party.
 From 2006 to 2009 he served as Deputy of the LX Legislature of the Mexican Congress representing Jalisco.

Question: What country of origin does Bill Squires and Alberto Salazar have in common?
Answer: American