I found this hard cover book and wasn’t really sure on what it was. So I called a friend and he said it was "a rare edition" and that I could get quite a bit of money out of it.
the back cover and the inside are printed with the following:
Advanced Dungeons and Dragons Monster Manual. Special Reference Work. 4th Edition, August, 1979. Hard Cover.
An alphabetical compendium of all the monsters found in advanced Dungeons & Dragons, including attacks, damage, special abilities, and descriptions.
By Gary Gygax 1977, 1978 -TSR Games
Gently used. Binding is in perfect condition. No rips, tears, or folds.
Over 350 Monsters This book provides a complete alphabetical listing of all "monsters" encountered in the various works which comprise the Advanced Dungeons & Dragons game system. It is an invaluable aid to players and dungeon masters alike!