T. Shevtsova, M. Kačániová, K. Garkava, J. Brindza, and J. Petrova, “CONTAMINATION OF BETULA VERRUCOSA EHRH. POLLEN BY MICROORGANISMS, MYCOTOXINS AND HEAVY METALS”, J microb biotech food sci, vol. 3, no. 6, pp. 509–513, Jun. 2014.