Scientific Technical Conference on "Environmental Protection in the Regions of Non-ferrous Metallurgy Works" (1st 1979 Plovdiv, Bulgaria)

• Pŭrva Nauchno-tekhnicheska konferent͡s︡ii͡a︡ s mezhdunarodno uchastie na tema "Opazvane na okolnata sreda ot zamursi͡a︡vane v raĭonite na deĭstvie na predprii͡a︡tii͡a︡ta ot t͡s︡vetnata metalurgii͡a︡"