- Author: William Arthur Lewis
- Language: English
- Year: 1949
- Author: Ettore Biocca
- Language: English
- Year: 1969
- Author: Rita Hinden (ed.)
- Language: English
- Year: 1945
- Author: Ludwig Klages
- Language: English
- Author: Frederick S. Perls
- Language: English
- Year: 1947
- Author: John Child
- Language: English
- Year: 1969
- Author: Sarvepalli Radhakrishnan
- Language: English
- Year: 1968
- Author: Allen J.R.L.
- Language: English
- Year: 1980