Bestandslücken
[N=1955,21-24; 1956,1-6,8-16,18-23; 1957,1-14,16-18,20-22,24; 1959,1-11,13-24; 1960; 1961; 1962,15-16; 1963,20; 1964 - 1966; 1967,1-8,10-14; 1968,2-24; 1969,1-11; 1970,3-4,6,8; 1971,12; 1972,2-4,10; 1973,9-12; 1974,1-11; 1975,4; 1976,3; 1977 - 1983]