V. . FRIŠTÁK, M. . VALOVČIAKOVÁ, M. . PIPÍŠKA, and J. . AUGUSTÍN, “Simultaneous and Sequential Extraction Protocols as Tools for Determination of Zinc Bioavailability in Dried Anaerobic Sludge”, Nova Biotechnol. Chim., vol. 11, no. 2, pp. 167–175, Dec. 2012.