1. T. N. Nazarchuk and O. I. Popova, Complexonometric Analysis of Metalloceramic and Ceramic Materials and Certain Alloys, Metallurgizdat, Moscow (1965), pp. 23–32.
2. S. P. Onosova, Zavod. Lab., 28: 271 (1962).
3. L. Ya. Polyak, Zavod. Lab., 27: 7 (1961).
4. G. Brunischolz and R. Cahen, Helv. Chim. Acta, 39: 324 (1956).
5. G. Brunischolz and R. Cahen, Helv. Chim. Acta, 39: 2135 (1956).