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2. Bauer, H. (1956). Ibid., 327, 491.
3. Bonting, S. L. (1955). Arch. Biochem., 58, 100.
4. Bueding, E., and Goldfarb, W. (1943). J. biol. Chem., 147, 33.
5. Bueding, E., and Goldfarb, W. and Wortis, H. (1940). Ibid., 133, 585.