1. Bessonov, A.S., Veterinariya, 1990, no. 4, p. 3.
2. FRG Patent no. 2 332 343, 1973; Ref. Zh., Khim., 1975, no. 17 O 130.
3. FRG Patent no. 2 332 398, 1973; Ref. Zh., Khim., 1975, no. 16 O 185.
4. FRG Patent no. 2 332 486, 1973; Ref. Zh., Khim., 1975, no. 23 O 165.
5. FRG Patent no. 2 332487, 1973; Ref. Zh., Khim., 1975, no. 17 O 131.