Bestandslücken
[N=1960,8-16,18-33,35-52; 1961,1-10,15-52; 1961; 1963; 1964,1-44,57-52; 1965,1-3,6-22,24-26,29-30,33-36,39-52; 1966,5-12,21-34,36-37,43-49; 1967,1-13,15-18,20-52; 1968; 1969; 1970, 1-11,13-24; 1971; 1972,30; 1973,13-14,19,25,32; 1974,8,18; 1976,4,18; 1977,3,23,25; 1978,4-5,13-14,25; 1979,1,12,23-24; 1980,1,4,15,20]