Author: Garson O'Toole
Alternate names: Gregory F. Sullivan
Bio: Garson O'Toole is the proprietor of the website "Quote Investigator" (2010-) and author of the 2017 book "Hemingway Didn't Say That." It is a pseudonym used by Gregory F. Sullivan, former computer scientist at Johns Hopkins University, with a doctorate in computer science from Yale.

Sources: Wikipedia & author's website (links below)

(Not to be confused with Gregory F. Sullivan, humanities professor at US Merchant Marine Academy and author of 2018 book "Regenerating Japan," VIAF ID 28152930869909671637 and OLID OL9717324A.)