- Author: Paul E. Gray, David DeWitt, A.R. Boothroyd, James F. Gibbons, Roberto Plana Abadía, Julián Fernández Ferrer
- Language: Spanish
- Year: 1970
- Author: Paul E. Gray, David DeWitt, A.R. Boothroyd, James F. Gibbons, Roberto Plana Abadía, Julián Fernández Ferrer
- Language: Spanish
- Year: 1970
- Author: David DeWitt
- Language: English
- Year: 2014
- Author: David Dewitt Hans Rattinger
- Language: English
- Year: 1991