On sale date from the publication date reported to the U.S. Copyright Office found in the Catalog of Copyright Entries, Third Series, Volume 22, Part 2, Periodicals, January-December 1968. Class B periodical. Copyright registration number B474865.
Palmer credits per interview: http://www.wtv-zone.com/silverager/interviews/palmer.shtml
Letters from Elaine M. Sciog, Dennis Allen, Henry Kinsey III, Mike Hudak, Achille Di Bacco and, "The Gifted One"; includes Know Ye These, the Hallowed Ranks of Marveldom.