How Ernest Hemingway's wartime experiences informed "In Our Time"

Daiker, Donald. “In Defense of Hemigway's Young Nick Adams: ‘Everything Was Gone to Hell Inside of Me.’” Texas Studies in Literature and Language, vol. 57, no. 2, 2015, pp. 242–257., doi:https://www.jstor.org/stable/26155300 .
This is an essay that, as its title implies, attempts to defend the character of Nick Adams from In Our Time. It begins by establishing that the character has received criticism over the years both in his morality and behavior, and for being a well-rounded, reasonable character, then analyzes passages, mostly from “The End of Something” and “The Three-Day Blow” to support the author’s points. Since Nick Adams is the main character of the collection of stories I will be explicating, detailed analysis of his character is relevant. The paper also cites some examples of the mentioned criticism in academia, which could be useful should the essay veer in that direction.
Hemingway, Ernest. Ernest Hemingway Selected Letters: 1917-1961. Ernest Hemingway Foundation, Inc., 1981.
This is perhaps the most important and relevant source to my specific essay, as it is a collection of letters, written by Hemingway, himself (some editions of the book list the only author as Hemingway, himself, though light research concluded that the letters were released in the 1970’s by his estate, then compiled by a third party for this book). Since my essay will analyze the author’s own personal experiences and how they informed his work, this seems to be the most direct and primary source for gathering information about Hemingway and his experiences.
Moddelmog, Debra. “The Unifying Consciousness of a Divided Conscience: Nick Adams as Author of ‘In Our Time.’” American Literature, vol. 60, Dec. 1988, pp. 591–610., doi:https://doi-org.aurarialibrary.idm.oclc.org/10.2307/2926659 .
This is an interesting article that seeks to address some critics of In Our Time that argue that Hemingway, at times, lost the thread of telling Nick Adams’s story, and inserted his own autobiographical information and anecdotes carelessly. The article analyzes Hemingway’s experiences that might have informed these moments, and his style, both of which seem useful in my own analysis. The critics cited here may also serve as good direction should I need more sources that might support this notion of autobiography that the author actually argues against, as well.
Vaughn, Elizabeth. “‘In Our Time’ as Self-Begetting Fiction.” Modern Fiction Studies, vol. 35, no. 4, 1989, pp. 707–716., doi:https://www.jstor.org/stable/26283371 .