- Author: Gregory Walters
- Language: English
- Year: 2023
- Author: Gregory Walters
- Language: English
- Year: 2018
- Author: Gregory Walters
- Language: English
- Year: 2013
- Author: Gregory Walters
- Language: English
- Year: 2013
- Author: Gregory Walters (auth.)
- Language: English
- Year: 2014