Azerbaijan S.S.R.) Nauchno-prakticheskai︠a︡ konferent︠s︡ii︠a︡ "Utilizat︠s︡ii︠a︡ otkhodov promyshlennosti i rudnykh mineralʹnykh mestorozhdeniĭ s t︠s︡elʹi︠u︡ okhrany okruzhai︠u︡shcheĭ sredy i ėkonomiki prirodnykh resursov (1989 Baku