1. Yoshimura, K., Waki, H., and Ohashi, S., Talanta, 1976, vol. 23, no. 3, p. 449.
2. Yoshimura, K. and Waki, H., Talanta, 1985, vol. 32, no. 5, p. 345.
3. Zolotov, Yu.A., Tsizin, G.I., Dmitrienko, S.G., and Morosanova, E.I., Sorbtsionnoe kontsentrirovanie mikrokomponentov iz rastvorov: primenenie v neorganicheskom analize (Adsorption Preconcentration of Trace Elements from Solutions: Application to Inorganic Analysis), Moscow: Nauka, 2007.
4. Brykina, G.D., Marchenko, D.Yu., and Shpigun, O.A., Zh. Anal. Khim., 1995, vol. 50, no. 5, p. 484 [J. Anal. Chem. (Engl. Transl.), vol. 50, no. 5, p. 440].
5. Bulatov, M.T. and Kaminkin, I.P., Prakticheskoe rukovodstvo po fotokolorimetricheskim i spektrofotomet-richeskim metodam analiza (Practical Guide to the Photocolorimetric and Spectrophotometric Methods of Analysis), Leningrad: Khimiya, 1986.