1. Y.J. Chen, J.H. Yang, X. Wu, T. Wu, Y.X. Luan, Talanta 58 (2002) 869.
2. B. Pal, P.K. Bajpai, T.S.B. Baul, Spectrochim. Acta 56A (2000) 2453.
3. S.H. Lee, J.K. Suh, M. Li, Bull. Korean Chem. Soc. 24 (2003) 45.
4. C.Z. Huang, Y.F. Li, Anal. Chim. Acta 500 (2003) 105.
5. W. Sun, K. Jiao, J.Y. Han, C.Z. Zhao, Acta Chim. Slov. 53 (2006) 367.