1. J. F. Clevenger, J. Amer. Pharmac. Assoc.17, 345 (1928).
2. T. Tusting Cocking undG. Middleton, Quart. J. Pharmac.5, 521 (1932) und8, 435 (1935).
3. O. Moritz, Arch. Pharmaz.276, 368 (1938); DRP. Nr. 696 342, Kl. 42, Gr. 1302; Apoth.-Ztg.55, 507 (1940) und56, 379 (1941).
4. H. Unger, Pharmaz. Ztg.81, 1400 (1936).
5. The Pharmacopoeia of the United States of America, XIVth Revision (1950).