Bender, Carl M.; Wu, Tai Tsun (1973-03-15). "Anharmonic Oscillator. II. A Study of Perturbation Theory in Large Order". Physical Review D. 7 (6). American Physical Society (APS): 1620–1636. Bibcode:1973PhRvD...7.1620B. doi:10.1103/physrevd.7.1620. ISSN0556-2821.
Bender, Carl M.; Wu, Tai Tsun (1973-03-15). "Anharmonic Oscillator. II. A Study of Perturbation Theory in Large Order". Physical Review D. 7 (6). American Physical Society (APS): 1620–1636. Bibcode:1973PhRvD...7.1620B. doi:10.1103/physrevd.7.1620. ISSN0556-2821.
Bender, Carl M.; Wu, Tai Tsun (1973-03-15). "Anharmonic Oscillator. II. A Study of Perturbation Theory in Large Order". Physical Review D. 7 (6). American Physical Society (APS): 1620–1636. Bibcode:1973PhRvD...7.1620B. doi:10.1103/physrevd.7.1620. ISSN0556-2821.