Proceedings of the Pennsylvania Academy of Science.

v.1; v.1-5 1924-1931; v.2-3; v.4-5; v.6-7; v.6-9 1932-1935; v.6-10 1932-1936; v.8-9; v.10-11; v.11-15 1937-1941; v.13-16 1939-1942; v.12-17 1938-43; v.16-20 1942-1946; v.17-20 1943-1946; v.21-24 1947-1950; v.18-25 1944-51; v.21-25 1947-1951; v.25-28 1951-1954; v.26-29 1952-55; v.29-32 1955-1958; v.30-32 1956-58; v.31-33 1957-1959; v.33-35 1959-1961; v.33-35 1959-61; v.34-36 1960-1962; v.36 1962; v.36-38 1962-65; v.38-39 1964-1966; v.39-42 1965-68; v.40-43 1966-1969; v.43-44; v.44 1970; v.44-45 1970-1971; v.45; v.45 1971; v.46-50 1972-1976; v.51-54 1977-1980; v.55-59 1981-1985; v.60-61 1986-1987; index