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.
When I first began to study Japanese seriously in 1975, I used this book together with the tapes. It offered everything what I could use around my postgraduate scholarship at a renowned Tokyo university. I did not need to study Japanese professionally, but basically wished to improve my conversational skills. In addition to conversation I wished to increase the number of kanji for everyday use that I could identify. I liked the lessons and felt that I slowly got a better grasp of everyday Japanese. I actually managed to eventually translate 5 short stories of a well-known writer all by myself with the help of a dictionary.