ISBN 9780441042913 books & textbook
People Minus X / Lest We Forget Thee Earth (Classic Ace Double, D-291)
Raymond Z. Gallun Calvin M. Knox (pseud Robert Silverberg)
Ace Books, Inc. /1958T Mass Market Paperback / 288 Pages
isbn-10: 0441042910 / isbn-13: 9780441042913
