1. Aro, A. and Alfthan, G., Analyst., 1995, vol. 120.
2. Golubkina, N.A. and Papazyan, T.T., Selen v pitanii. Rasteniya, zhivotnye, chelovek (Selenium in Nutrition. Plants, Animals, Humans), Moscow: Izd. Belyi Gorod, 2006.
3. Schrauzer, G.N., Adv. Food Nutr. Res., 2003, vol. 47.
4. Alfthan, G., Anal. Chim. Acta, 1984, vol. 65.
5. Koivistoinen, P., Acta Agric. Scand., 1980, suppl. 2, vol. 22.