P-ISSN 0002-9599
E-ISSN 1945-452X
Vol. s4-48, Issue 288, 1919December 01, 1919 EDT
The Middle Ordovician of Central and South Central Pennsylvania
The Middle Ordovician of Central and South Central Pennsylvania
Richard Montgomery Field,
Field, R. M. (1919). The Middle Ordovician of Central and South Central Pennsylvania. American Journal of Science, s4-48(288), 403–428. https://doi.org/10.2475/ajs.s4-48.288.403