1. Authors' Certificate 123,287; USSR, RZh Khimiya, No. 17, No. 10794P (1960).
2. Authors' Certificate 124,590; USSR, RZh Biologiya, No. 3, No. 358P (1978).
3. Authors' Certificate 130,626; USSR, RZh Khimiya, No. 5, No. 0237P (1979).
4. Authors' Certificate 136,858; USSR, ibid., No. 16, No. 0190P.
5. Authors' Certificate 167,609; USSR, ibid., No. 16, No. 558P.