Geological Survey occasional paper.

1-9 (1974); no.1-10 1974-1975; no.1-20 1974-76; 10-19 (1975-76); no.11-20 1975-1976; no.21-25; no.24 1978; 20-28 (1976-79); no.21-31 1977-80; no.26-30 1978-1980; no.25-35 1978-1981; 29-36 (1980-82); no.31-36 1980-1982; no.32-39 1980-82; no.36-41 1982-1983; no.37-41 1982-1983; 37 (1983); 38-46 (1982-84); no.40-50 1983-85; no.42-49 1984-1985; no.42-52 1984-1986; 47-53 (1985-86); no.50-52, 54-59; no.51-55 1986-1989; no.53-60 1986-1991; 54-56 (1988-91); no.61 1992; 57-64 (1991-94); no.56-64 1991-1994; no.60-64 1991-1994; no.62 1994; no.63 1994; no.67 2004