Bogdanova Popov, Biljana, Vesna Karapetkovska Hristova, Stefce Presilski, Muhhamad Ali Shariati, and Stevo Najman. 2017. “Assessment of Heavy Metals in Propolis and Soil from the Pelagonia Region, Republic of Macedonia”. Macedonian Journal of Chemistry and Chemical Engineering 36 (1):23-33. https://doi.org/10.20450/mjcce.2017.1004.