As I began doing research, I found this biography on Hemingway. While this is not my section of research, I thought it may be helpful for others doing biographical to compare different websites.
This site identifies the book the story was orginally published in as well as some criticism of the story.
The sources page has what look to be good sources on criticism in the time period but our databases don't go back to 1927 in those journals - I tried.
I found this article through our library database. Under "subject" I clicked on "Literature Resource Center," typed in "Hemingway" in the search bar, and found this article under "Hemingway's Hills Like White Elephants." This explains Hemingway's techniques as a writer and what he wants his audience to understand through the story.
Link, Alex. "Staking Everything on it: A Stylistic Analysis of linguistic Patters in "Hills like White Elephants." Hemingway Review. Vol. 23. Issue 2 Spring 2004. pg 66-74