- Author: John Tincey Keith Roberts
- Language: English
- Author: Ralph R. Roberts Joe Kraynak
- Language: English
- Year: 2007
- Author: Douglas S. Roberts
- Language: English
- Year: 2008
- Author: Ralph R. Roberts Lois Maljak Paul Doroh Joe Kraynak
- Language: English
- Year: 2008
- Author: Jeremy A. Roberts Zinnia Gonzalez-Carranza
- Language: English
- Year: 2007
- Author: M. J. D. Roberts
- Language: English
- Year: 2004
- Author: Mark Cade Simon Roberts
- Language: English
- Year: 2002
- Author: Philip Heller Simon Roberts
- Language: English
- Year: 2002
- Author: Philip Heller Simon Roberts
- Language: English
- Year: 2002