1. 1) F. Nebl: St. u. Ei. 33 (1952) 773
2. 2) Gregg and Daniloff: The Alloys of Iron and Copper (1934) 90
3. Cameron & Watherhouse: J. of I. and St. Inst. 113 (1926) 355
4. B. Herbert u. R. Pusch: St. u. Ei. 73 (1953) 204
5. 3) Loring & MacLaren: The Alloys of Iron and Copper (1934) 82