Atabekyan, L.V., et al. “ELEMENT COMPOSITION OF BARBERRY ($BERBERUS$ L.) AND DEAF NETTLE ($LAMIUM~ALBUM$ L.) LEAVES”. Proceedings of the YSU B: Chemical and Biological Sciences, vol. 48, no. 1 (233), Mar. 2014, pp. 28-31, doi:10.46991/PYSU:B/2014.48.1.028.