1. Bohr A. and Mottelson B. R., Nuclear Structure, Vol. II (Benjamin, New York) 1975.
2. Nilsson S. G., Mat. Fys. Medd. Dan. Vid. Selst, 29, no. 16 (1955).
3. Bogoliubov N. N., Sov. Phys. JETP, 7 (1958) 41; Nuovo Cimento, 7 (1958) 794.
4. Valatin J. G., Nuovo Cimento, 7 (1958) 843.
5. Rowe D. J., Nuclear Collective Motion (Methuen and Co. Ltd., London) 1970.