Ivanov, Christo; Tcholakova, Tsvetanka
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Ahmed, M. G.; Ahmed, S. A.; Bahar, M. H.; Khondaker, M. A.; Islam, M. A.; Anam, A. K. M. M.
Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1982 , vol. 21, # 5 p. 470 - 471