- Author: Duffield Nicola
- Language: English
- Year: 2013
- Author: Duffield John S.
- Language: English
- Author: Vernon Hewitt Mark Duffield
- Language: English
- Year: 2009
- Author: Mark Duffield
- Language: Italian
- Year: 2004
- Author: Mark Duffield
- Language: Italian
- Year: 2004
- Author: Richard Gordon Chris DUFFIELD Ph.D Vickie Wickhorst Ph.D.
- Language: English
- Year: 2013
- Author: Richard Gordon Chris DUFFIELD Ph.D Vickie Wickhorst Ph.D.
- Language: English
- Year: 2013
- Author: Vicki L. Birchfield John S. Duffield (eds.)
- Language: English
- Year: 2011
- Author: Vicki L. Birchfield John S. Duffield (eds.)
- Language: English
- Year: 2011