- Author: Bender Wu.
- Language: English
- Year: 1969
- Author: Francisco J. Yndurain
- Language: English
- Year: 2006
- Author: Bialynicki-Birula I.
- Language: English
- Year: 1970
- Author: Dirac P.A.M.
- Language: English
- Year: 1948
- Author: Percy Williams Bridgman
- Language: English
- Year: 1915
- Author: Percy Williams Bridgman
- Language: English
- Year: 1935