- Author: John Cresswell John Hartley
- Language: English, Esperanto
- Year: 1968
- Author: King Palmer
- Language: English
- Year: 1952
- Author: A.R.Burn Συλλογικό
- Language: English
- Year: 1947
- Author: Henry Raymond Williamson
- Language: English
- Year: 1974
- Author: Daisy Valerie Perrott
- Language: English
- Year: 1957
Spanish
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- Author: Norman Scarlyn Wilson
- Language: English
- Year: 1939
- Author: T. Grahame Bailey
- Language: English
- Year: 1962
- Author: Christopher Shackle
- Language: English
- Year: 1972
- Author: Marsack C. C.
- Language: English
- Year: 1962
- Author: Burgers M. P. O.
- Language: English
- Year: 1957