My First Experience with the Great Logician by Jacques Futrelle Evidence by Murray Leinster The Adventures of the Diamond Necklace by G. F. Forrest The Purloined Letter by Edgar Allan Poe The Nameless Man by Rodrigues Ottolengui The Clue of the Silver Spoons by Robert Barr The Tin Box by Herbert Keen The Mysterious Case by Anna Katharine Green Cheating the Gallows by Israel Zangwill The Great Ruby Robbery by Grant Allen
Various is the correct author for any book with multiple unknown authors, and is acceptable for books with multiple known authors, especially if not all are known or the list is very long (over 50).
If an editor is known, however, Various is not necessary. List the name of the editor as the primary author (with role "editor"). Contributing authors' names follow it.
Note: WorldCat is an excellent resource for finding author information and contents of anthologies.