- Author: Walker Mark
- Language: English
- Year: 2013
- Author: Walker Mark
- Language: English
- Year: 2013
- Author: Charls E. Walker Mark A. Bloomfield (eds.)
- Language: English
- Year: 1987
- Author: Mark J. Walker Mark J. Walker
- Language: English
- Year: 2012
- Author: Mike Carlton, Richard Walker, Mark Hamlyn, Gail Jarvis, Jacomiene Betlem, All authors
- Language: English