1. J. D. WEINFORDNER, Trace Analysis Spectroscopic Methods for Elements, John Wiley and Sons, 1970.
2. V. B. RYABININ, I. L. AGAFONOV, N. V. LARIN, Poluch. Anal. Chist.-Veschestv., 1 (1976) 51.
3. R. A. FASSEL, Anal. Chem., 32 (1960) 19A.
4. R. M. DIXIT, Bull. Mater. Sci., 3 (1981) 371.
5. L. V. AGAPOVA, A. V. ANTONOV, N. V. TRONEV, N. V. BAGAEV, Zavod. Lab., 47 (1981) 45.