- Author: David Porter David S. G. Stirling
- Language: English
- Year: 1991
- Author: David Porter David S. G. Stirling
- Language: English
- Year: 1990
- Author: David Porter David S. G. Stirling
- Language: English
- Year: 1991
- Author: David Porter David S. G. Stirling
- Language: English
- Year: 1991