TY  - BOOK
AU  - Swartz,Frank M.
TI  - The Helderberg group from central Pennsylvania to southwestern Virginia,
AV  - QE728 .S9
PY  - 1929///
PB  - State College, Pa., School of mineral industries
KW  - Paleontology
KW  - United States
KW  - Devonian
N1  - [pt. 1] "reprinted from the Proceedings of the Pennsylvania academy of science, v. 3, 1929."; Contains references
ER  -