[Cooperation of countries that are members of the Council of Economic Mutual Assistance in the field of atmospheric hygiene].
D000397:Air Pollution / Q000517:prevention & control*; D002031:Bulgaria; D003604:Czechoslovakia; D005859:Germany, East; D007391:International Cooperation; D011044:Poland; D012383:Romania; D014586:USSR
Sotrudnichestvo stran--chlenov SEV--v oblasti gigieny atmosfernogo vozdukha.