- Author: Washek F. Pfeffer
- Language: English
- Year: 2001
- Author: Washek F. Pfeffer
- Language: English
- Year: 2012
- Author: Washek F. Pfeffer
- Language: English
- Year: 2012
- Author: Washek F. Pfeffer
- Language: English
- Year: 1994
- Author: Washek F. Pfeffer
- Language: English
- Year: 1993