frankfurt,1972 (2) frankfurt,1973 frankfurt,1974 (3) frankfurt,1976 frankfurt,1977 (2) frankfurt,1979 (2) frankfurt,1981 frankfurt,1982 (2) frankfurt,1983 frankfurt,1984 (2) frankfurt,1985 (2) frankfurt,1986 (3) frankfurt,1987 (5) frankfurt,1988 frankfurt,1989 frankfurt,1990 (5) frankfurt,1991 (7) frankfurt,1992 (4)