1. Akert, K., W. P. Koella and R. Hess jr. Amer. J. Physiol. 168, 260 (1952).
2. Aschoff, J.: Pflügers Arch. 254, 262 (1951).
3. Ber. ges. Physiol. 154, 266 (1952).
4. Ban, T., H. Masai, A. Sakai and T. Korotsu: Med. J. Osaka Univ. 2, 145 (1941)
5. Bjerner, B.: Acta physiol. scand. (Stockh.) Suppl. 65 in Bd 19, (1949).