The Last Castle / World of the Sleeper

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Overview:

Title: The Last Castle / World of the Sleeper
Author: Jack Vance, Tony Russell Wayman
Year: 1967
Publisher: Ace Books
Price: $0.60
Pages: 71+184
Binding: dos
Type: Omnibus
Title Reference: World of the Sleeper
Notes:
- The Last Castle by Jack Vance
  - Cover and art credited to "Jack Gaughan"
  - The Last Castle 71 pages.
  - Frontispiece continues on the title page (page 3).
- World of the Sleeper by Tony Russell Wayman
  - Cover art credited to "Jack Gaughan"
  - Interior art signed with Jack Gaughan's initials.
  - World of the Sleeper 184 pages.
- Published 7/67 per Double Your Pleasure by James A. Corrick
- Published 8/67 per the second printing (In Ace Double #16641) "First Ace printing: August, 1967"