Propolis produced in Bulgaria and Mongolia: phenolic compounds and plant origin V. Bankova, A. Dyulgerov, S. Popov, L. Evstatieva, L. Kuleva, O. Pureb and Z. ZamjansanApidologie, 23 1 (1992) 79-85DOI: https://doi.org/10.1051/apido:19920109
