1. Mystery of the Ancients (A Gamma World Adventure Book) (An Endless Quest Book #28)
by Simon, Morris 
Price: USD 64.99
Dealer: Abebooks, Second Chance Books & Comics
Description: ISBN10: 0880382171, ISBN13: 9780880382175, [publisher: T S R, Incorporated, Lake Geneva, WI, USA] Softcover Mass Market Paperback [Yukon, OK, U.S.A.] [Publication Year: 1985]  

2. Mystery of the Ancients Endless Quest Book 28 / A Dungeons & Dragons Adventure Book
by Simon Morris 
Price: USD 144.29
Dealer: Biblio, CKBOOKS
Description: TSR, Date: 1985. 1st Printing. Mass Market Paperback. Very Good. uncreased, very old pricing sticker on front cover, light bumping around edges of cover, light foxing to page edges 1985. TSR ISBN 0880382171 9780880382175 [US] 

3. Mystery of the Ancients (Endless Quest, Book 28 / A Dungeons & Dragons Adventure Book)
by Simon, Morris 
Price: USD 150.30
Dealer: Abebooks, CKBooks
Description: ISBN10: 0880382171, ISBN13: 9780880382175, [publisher: TSR] Softcover uncreased, very old pricing sticker on front cover, light bumping around edges of cover, light foxing to page edges [Bussey, IA, U.S.A.] [Publication Year: 1985]  

4. Mystery of the Ancients (an Endless Quest Book #28)
by Simon, Morris 
Price: USD 175.00
Dealer: Alibris, The Book Junction via Alibris
Description: TSR 1985 First Printing Paperback VG in na jacket Some rubbing & edgewear; couple light creases; tiny chip & scuff on bottom edge; yellowing; overall clean & tight. 157 pages. 

5. Mystery of the Ancients An Endless Quest Book #28
by Simon Morris 
Price: USD 175.00
Dealer: Biblio, The Book Junction
Description: TSR, Date: 1985. Paperback. VG/na. some rubbing & edgewear; couple light creases; tiny chip & scuff on bottom edge; yellowing; overall clean & tight. 157 pages 1985. TSR ISBN 0880382171 9780880382175 [US] 

6. Mystery of the Ancients (An Endless Quest Book #28)
by Simon, Morris, Illustrated by: 
Price: USD 175.00
Dealer: Abebooks, The Book Junction
Description: ISBN10: 0880382171, ISBN13: 9780880382175, [publisher: TSR] Softcover some rubbing & edgewear; couple light creases; tiny chip & scuff on bottom edge; yellowing; overall clean & tight. 157 pages [Shippensburg, PA, U.S.A.] [Publication Year: 1985]