A Guide to Barsoom, The Mars of Edgar Rice Burroughs, John Flint Roy, Ballantine Books, 1976 1st paperback. BB# 345-24722-1-175, first paperback. Cover illustration by Boris Vallejo, interior illustrations by Neal MacDonald, 200 pages. Very Good. Edge wear and light soiling to all panels, strong cover with one blemish over the first two letters in the “fully illustrated” slug on the lower inside edge. Spine has light crease but it not sunned or faded. Clean pages.