- Author: Douglas W. Hubbard Richard Seiersen
- Language: English
- Year: 2016
- Author: Douglas W. Hubbard
- Language: English
- Year: 2014
- Author: Douglas W Hubbard
- Language: English
- Year: 2009
- Author: Douglas W. Hubbard
- Language: English
- Year: 2011
- Author: Douglas W Hubbard
- Language: English
- Year: 2009
- Author: Douglas W. Hubbard
- Language: English
- Year: 2010
- Author: Douglas W. Hubbard
- Language: English
- Year: 2009
- Author: Douglas W. Hubbard
- Language: English
- Year: 2007
- Author: Douglas W. Hubbard
- Language: English
- Year: 2010
- Author: Douglas W. Hubbard
- Language: English
- Year: 2007