Tham khảo Sinh sản cơ hội

    • WE Duellman, L Trueb. Biology of amphibians. The Johns Hopkins University Press, 1994, p. 20
    • Malpoux B. The Neuroendocrine Control of Seasonal Rhythms. In: Conn PM, Freeman ME, ed., Neuroendocrinology in physiology and medicine. Humana Press, 1999, p. 437
    • Martin R, Johnson P. Bennett's Tree-kangaroo. In: R. Straham, ed., Mammals of Australia, Washington, DC: Smithsonian Institution Press, 1995, pp. 307–8, PMID 16026787
    • H.B. Tordoff; W.R. Dawson (1965). "The influence of daylength on reproductive timing in the red crossbill". The Condor. 67 (5): 416–22. doi:10.2307/1365634. JSTOR 1365634.
    • T.P. Hahn (1995). "Integration of photoperiodic and food cues to time changes in reproductive physiology by an opportunistic breeder, the red crossbill, Loxia curvirostra (Aves: Carduelinae)". J. Exp. Zool. 272: 213–26. doi:10.1002/jez.1402720306.
    • U. Shanas; A. Haim (2004). "Diet salinity and vasopressin as reproduction modulators in the desert-dwelling golden spiny mouse (Acomys russatus)" (PDF). Physiology and Behavior. 81 (4): 645–50. doi:10.1016/j.physbeh.2004.03.002. PMID 15178158.
    • Wayne NL, Rissman EF (1990). "Environmental regulation of reproduction in an opportunistic breeder: the musk shrew (Insectivora: Suncus murinus)". Prog. Clin. Biol. Res. 342: 668–72. PMID 2381955.
    • Fleming, P. A., and S. W. Nicolson. "Opportunistic breeding in the Cape spiny mouse (Acomys subspinosus)." African Zoology 37.1 (2002): 101-105.