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.
I often listen to this programme on RTE and this selection from the early noughties seemed ideal as a quick dip holiday read. Each calendar month has its own chapter as the weekly broadcast is usually thematic, although articles can be inspired by just about anything. Personal reminiscence is the usual, with coming of age stories of trips to the seaside, hometown blues, absent friends and first steps on the property ladder. Short biographies and historical events are also part of the weave. This sounds ordinary when put so bluntly, but these are almost always engaging tales, with a myriad of different perspectives and a good seasoning of wit. Leo Cullen does, I think, win out in terms of quantity, but quality and variety too. From touching vignettes of the dear departed to a brilliant and hilarious dog’s POV of the world. Vona Groarke also stands out. Better known as a poet she brings those lyrical sensibilities to her perfictly formed essays on growing up and growing old. There’s literary and vernacular, old familiar and new voices. Besides the mellow enjoyment there’s a very useful streak in this book. As a writer, it was inspiring to see such a broad array of talent, and to marvel at how each could conjure a story from out of thin air. I know, I know, there’s a lot of research and a thousand sketches of experience goes into it too. I would highly recommend this to the writer, especially the tyro writer, and the discerning reader should love it too.