The first edition of Dinosaurs has the letters ABCDEFG on page 160. © 1990 by Western Publishing Company, Inc. Illustrations © 1990 by John D. Dawson. Published by Golden Press, New York, N.Y. No cover price. The ISBN number on the back cover is 0-307-24076-2. Listed as a Golden Guide on the cover and the inside front cover.
No cover variant or revised Golden Press edition exists that I am aware of. This title is still in print by St. Martin's Press.