- Author: Wrede Robert C, Spiegel Murray R
- Language: English
- Year: 2001
- Author: Spiegel Murray R., Wrede Robert C
- Language: English
- Year: 2011
- Author: Spiegel Murray, Wrede Robert C
- Language: English
- Year: 2001
- Author: Spiegel Murray, Wrede Robert C
- Language: English
- Year: 2002
- Author: Spiegel Murray, Wrede Robert C
- Language: English
- Year: 2002
- Author: Wrede Robert Clinton
- Language: English
- Year: 1972
- Author: Wrede Robert Clinton
- Language: English
- Year: 1972