H52A1968H52A1969H52A1970H52A1971H52A1972H52A1973H52A1974H52A1975H52A1976H52A1977H52A1978H52A1979H52A1980H52A1981H52A1982H52A1983H52A1984H52A1985H52A1986H52A1987