Jeffrey M. "Jeff" Shaara (born February 21, 1952) is an American novelist, the son of Pulitzer Prize winner Michael Shaara.
The Guns of August (1962), also published as "August 1914", is a volume of history by Barbara W. Tuchman.
 It is centered on the first month of World War I.
 After introductory chapters, Tuchman describes in great detail the opening events of the conflict.
 Its focus then becomes a military history of the contestants, chiefly the great powers.
Gone for Soldiers is a 2000 historical novel by Jeffrey Shaara about the Mexican-American War.
 It was written as a stand-alone novel, but could also be seen as a prequel to the Civil War trilogy written by Shaara and his father, Michael Shaara, introducing some of the key protagonists in the campaigns that first won them fame.
 The action begins with the Battle of Vera Cruz and follows Winfield Scott and his army as they march toward Mexico City, including the Battle of Cerro Gordo and culminating in the Battle of Chapultepec and the fall of Mexico City.
"Soldier Boy" (also known as "X Minus One #71: 56-10-17 Soldier Boy") is a 1953 science fiction short story by American author Michael Shaara, about a soldier who, when sent on a routine patrol to a colonized world, saves the planet from an alien and its robot attack devices.
 Despite an ingrained contempt for the military that arose as part of conditioning to avoid war, the human colonists gradually assist the soldier when strange occurrences suggest they are not alone on the planet and may be, like several other colony planets, under threat of extermination by outside forces.
 It was originally published in the July 1953 issue of "Galaxy Science Fiction".
 It is also the title of a 1982 collection of Shaara's short stories
Barbara Wertheim Tuchman ( ; January 30, 1912 – February 6, 1989) was an American historian and author.
 She won the Pulitzer Prize twice, for "The Guns of August" (1962), a best-selling history of the prelude to and the first month of World War I, and "Stilwell and the American Experience in China" (1971), a biography of General Joseph Stilwell.
Philip Lee Williams (born January 30, 1950) is an American novelist, poet, and essayist noted for his explorations of the natural world, intense human relationships, and aging.
 A native of Athens, Georgia, he grew up in the nearby town of Madison.
 He is the winner of many literary awards including the 2004 Michael Shaara Prize for his novel "A Distant Flame" (St. Martin’s), an examination of southerners who were against the Confederacy’s position in the American Civil War.
 He is also a winner of the Townsend Prize for Fiction for his novel "The Heart of a Distant Forest", and has been named Georgia Author of the Year four times.
 In 2007, he was recipient of a Georgia Governor’s Award in the Humanities.
 Williams's "The Divine Comics: A Vaudeville Show in Three Acts", a 1000-page re-imagining of Dante's magnum opus, was published in the fall of 2011.
 His latest novel, Emerson's Brother, came out in May 2012 from Mercer University Press
Gettysburg is a 1993 American epic war film written and directed by Ronald F. Maxwell, adapted from the historical novel "The Killer Angels" (1974) by Michael Shaara, about the Battle of Gettysburg during the American Civil War.
 The film stars Tom Berenger, Jeff Daniels, and Martin Sheen; its score was composed by Randy Edelman.
 The film "Gods and Generals" is an adaptation of the 1996 novel of the same name by Jeffrey Shaara and was filmed as a prequel to Maxwell's "Gettysburg".
Michael Shaara (June 23, 1928 – May 5, 1988) was an American author of science fiction, sports fiction, and historical fiction.
 He was born to Italian immigrant parents (the family name was originally spelled Sciarra, which in Italian is pronounced in a similar way) in Jersey City, New Jersey, graduated in 1951 from Rutgers University, where he joined Theta Chi, and served as a sergeant in the 82nd Airborne Division prior to the Korean War.
Gods and Generals is a novel which serves as a prequel to Michael Shaara's 1974 Pulitzer Prize-winning work about the Battle of Gettysburg, "The Killer Angels".
 Written by Jeffrey Shaara after his father Michael's death in 1988, the novel relates events from 1858 through 1863 during the American Civil War, ending just as the two armies march toward Gettysburg.
 Since 1988, Jeff Shaara has written "The Last Full Measure", which follows the events presented in "The Killer Angels".
The March of Folly: From Troy to Vietnam is a book by Barbara W. Tuchman, an American historian and author.
 It was published on March 19, 1984 by Knopf in New York.

Question: Are both Barbara W. Tuchman and Michael Shaara American?
Answer: yes