Holdings
1960,4-5; 1961,7-8; 1963,13; 1964,2; 1965,3-4; 1966,6; 1968,12; 1969,2u.4; 1970,5; 1971,8-10; 1972,3-5; 1973,9; 1974,13-15; 1975,16-18; 1976,2-5; 1977,6-9; 1978,11-13; 1979,15-16; 1980,3u.6-7; 1981,8-11; NEUE FOLGE: 1981,3u.4u.6; 1982,7-10; 1983,11-14; 1984,16-18; 1985,19-23; 1986,2-3u.24-25; 1987,4-6; 1988,7-8; 1988/89,10; 1989,13