METHOD OF PROCESSING SPENT ZINC SULFATE SOLUTIONS - POPOV BORIS A,SU; IVAKIN ANATOLIJ F,SU; CHEKHOMOVA LYUBOV F,SU; KHALTURIN VYACHESLAV A,SU; SOLOSHENKO ALEKSANDRA A,SU; ZAKUTINSKIJ VLADIMIR L,SU; KRAVCHENKO GALINA A,SU; RYABIN VIKTOR A,SU (1990)