The Secret of the Time Vault ( Perry Rhodan 6 )

( German - Das Geheimnis der Zeitgruft - 1961 )

novel by Walter Ernsting ( as Clark Dalton )

Pubished: Ace Books - paperback - 1971 ( rep. 1972, 1974 ) ( US )
ISBN: none

Orbit - paperback - 1975 ( UK )
ISBN: 0860078426 / 9780860078425