Pure Appl. Chem., 1970, Vol. 24, No. 2, pp. 361-392
http://dx.doi.org/10.1351/pac197024020361
The angular overlap model of the ligand field: theory and applications
First page:

Pure Appl. Chem., 1970, Vol. 24, No. 2, pp. 361-392
http://dx.doi.org/10.1351/pac197024020361