S. B. Goldhaber, “Trace element risk assessment: essentiality vs. toxicity,” Regul. Toxico. Pharm., vol. 38, pp. 232–242, 2003.
 K. Lee, F. M. Clydesdale, “Iron sources for food fortification and their changes due to food processing,” CRC Cr. Rev. Food Sci., vol. 11, pp. 117–153, 1978.
 A. Quinteros, R. Farre´, M.J. Lagarda, “Optimization of iron speciation (soluble, ferrous and ferric) in beans, chickpeas and lentils Food Chemistry,” Food Chem. vol. 75, pp. 365–370, 2001.
 J.F. Van Staden, L.V. Mulaudzi, R.I. Stefan, “Speciation of Mn(II) and Mn(VII) by on-line spectrophotometric sequential injection analysis,” Anal. Chim. Acta, vol. 499, pp. 129–137, 2003.
 Z. Sabatkova, M. Safarikova, I. Safarik, “Magnetic ovalbumin and egg white aggregates as affinity adsorbents for lectins separation’ Biochem. Eng. J., vol.40, pp. 542–545, 2008.
 Z.F. Wang, H.S. Guo, Y.L. Yu, N.Y. He, “Synthesis and characterization of a novel magnetic carrier with its composition of Fe3O4/carbon using hydrothermal reaction,” J. Magn. Magn. Mater, vol. 302, pp. 397-404, 2006.
 Y. Li, Y.C. Liu, J. Tang, H.Q. Lin, N. Yao, X.Z. Shen, C.H. Deng, P.Y. Yang, X.M. Zhang, “[email protected]
magnetic core–shell microspheres for rapid and highly specific capture of phosphopeptides with mass spectrometry analysis,” J. Chromatogr. A, vol. 1172, pp. 57-71, 2007.
 D. Creanga, G. Calugaru, “Physical investigations of a ferrofluid based on hydrocarbons,” J. Magn. Magn. Mater. vol. 289, pp. 81–83, 2006.