I'm a flash-fiction aficionado, so I read quite a few collections of sudden and micro fiction. This collection includes authors that are best known for their longer book-length, television, or stage works: Graham Greene, Samuel Clemens, Aldous Huxley, August Strindberg, Richard Matheson, Dorothy Parker, Herman Melville, E.B. White, and so many others. Since you really don't need to read these in any particular sequence, some of my favorites were:
"The Upturned Face" by Stephen Crane. Excellent, evocative elegance.
"Absent-Mindedness in a Parish Choir" by Thomas Hardy. I'm not even a Hardy fan!
"A Question of Blood" by Ernest Haycox. Terrific character study.