Activity report.

1st 1971/72; no.1 1971/1972; 2nd 1973; 2d 1973; no.2 1973; 3rd 1974; 3d 1974; no.3 1974; 1972-75; 4th 1975; no.4 1975; 1st-5th 1971-76; 5th 1976; no.5 1976; 6th 1977; no.6 1977; 7th 1978; no.7 1978; no.1-8 1971/72-1979; 1976-79; 8th 1979; no.8 1979; v.10(1981); v.11(1982); v.1(1973); v.12(1983); v.13(1984); v.14(1985); v.15(1986); v.3(1974); v.4(1975); v.5(1976); v.6(1977); v.7(1978); v.8(1979); v.9(1980); v.17(1988); v.16(1987)