Penzler, Otto. Hang gliding : riding the wind / by Otto Penzler. - Mahwah, NJ : Troll, 1976. - 32 p. : ill. Text and photographs explore the sport of hang gliding and describes the different gliders used. LCCN: 75021843 Subjects--Topical Terms: Gliding and soaring. Dewey Class. No.: 797.5