Pennsylvania caves,
Stone, Ralph W. 1876-1964.
Pennsylvania caves, by Ralph W. Stone. - Harrisburg, Department of internal affairs, Topographic and geologic survey, 1930. - 63 p. incl. illus., maps. 23 cm. - Pennsylvania. Geological survey (4th, 1919- ) Bulletin G3 . - Bulletin G, 3. .
Bibliographical footnotes.
gs 30000221
Caves.
GB605.P4 / S7
PY G345/4.3 G3
Pennsylvania caves, by Ralph W. Stone. - Harrisburg, Department of internal affairs, Topographic and geologic survey, 1930. - 63 p. incl. illus., maps. 23 cm. - Pennsylvania. Geological survey (4th, 1919- ) Bulletin G3 . - Bulletin G, 3. .
Bibliographical footnotes.
gs 30000221
Caves.
GB605.P4 / S7
PY G345/4.3 G3