Existencias: 1972 v. 72, no. 10, 12; 1973 v. 73, no. 12; 1980 v. 80, no. 6, 9, 12; 1981 v. 82, no. 4, 5, 8, 11; 1983 v. 83, no. 1, 2, 4, 5; 1984 v. 84, no 3; 1985 v. 85, no. 1-4; 1986 v. 86, no. 1, 3, 4, 5; 1987 v. 87, no. 1, 2, 5; 1988 v. 88, no. 1, 4, 5, 6; 1989 v. 89, no. 1; 1990 v. 90 1, 2, 3, 6, 8; 1991 v. 91, no. 1, 2, 3, 4, 6; 1992 v. 92, no. 1, 2; 1993 v. 93, no. 1,2; 1994 v. 94, no. 1-4, 6, 7; 1996 v. 96 1-4