- Author: Peter Ritchie (auth.)
- Language: English
- Year: 2016
- Author: Marilee Coles-Ritchie (auth.)
- Language: English
- Year: 2009
- Author: Nick Ritchie (auth.)
- Language: English
- Year: 2012
- Author: L. David Ritchie (auth.)
- Language: English
- Year: 2006
- Author: Alain Guyomarch Howard Machin Ella Ritchie (auth.)
- Language: English
- Year: 1998
- Author: Marilee Coles-Ritchie (auth.)
- Language: English
- Year: 2009
- Author: G. J. Ritchie (auth.)
- Language: English
- Year: 1993
- Author: T. H. Pennington D. A. Ritchie (auth.)
- Language: English
- Year: 1975
