Report of investigations.

no.1-6 (1965-68); no.1-10 1965-69; no.7-12 (1968-70); no.11-16 1969-71; no.13-16 (1970-71); no.17-19 1971-73; no.17-21 (1971-74); no.22-26 (1974-75); no.20-29 1973-78; no.30-34 1979-81; no.32-35 (1979-83); no.35-37 1982-83; no.36-40 (1982-84); no.41-43 1985; no.44-46 1986; no.43-49 1985-88; no.49-51 (1988-89); no.50-52 1988-1989; no.52-54 (1990-91); no.55-58 (1992-93); no.60-61 1996; v.19-26(1973-1975); c.1 no.63; c.1 no.72