D. A. Clabo, W. D. Allen, R. B. Remington, Y. Yamaguchi, and H. F. Schaefer III, “A systematic study of molecular vibrational anharmonicity and vibration-rotation interaction by self-consistent-field higher-derivative methods – asymmetric-top molecules,” Chem. Phys., 123 (1988) 187-239. DOI: 10.1016/0301-0104(88)87271-9
