Index to Volumes 11-20

From Author Wars - https://authorwars.com/books/index-to-volumes-11-20-133000.html

Overview:

Title: Index to Volumes 11-20
Author: uncredited
Year: 1978
Type: Essays

Editions/Publications:

Unknown. Orbit 20 (Unknown, uncredited, Harper & Row, ISBN-10: 0060124296, $9.95, 248 pages, Hardcover, Anthology)