1) KANAI, M., RAZ, A., and GOODMAN, D. S. (1968): Retinol-binding protein; the transport protein for vitamin A in human plasma. J. Clin. Invest., 47, 2025-2044.
4) TAYLOR, A. C., and KOLLROS, J. J. (1946): Stages in the normal development of Rana pipiens larvae. Anat. Rec., 94, 7-24.
5) ASHLEY, H., KATTI, P., and FRIEDEN, E. (1968): Urea excretion in the bullfrog tadpole; effect of temperature, metamorphosis, and thyroid hormones. Dev, Biol., 17, 293-307.