Letters (Perry Rhodan #523)
From Author Wars - https://authorwars.com/books/letters-perry-rhodan-523-1958723.html
Editions/Publications:
- 1971 . Perry Rhodan, #523: Die Planetenräuber (1971, various, Moewig, DM 1.00, 68 pages, digest, MAGAZINE)
- 1971 . Perry Rhodan, #289: Das System der blauen Riesen (1971, various, Moewig, DM 1.00, 68 pages, digest, MAGAZINE)