PT  - JOURNAL ARTICLE
AU  - Stevenson, John James
TI  - The upper Devonian rocks of southwest Pennsylvania
AID  - 10.2475/ajs.s3-15.90.423
DP  - 1878 Jun 01
TA  - American Journal of Science
PG  - 423--430
VI  - s3-15
IP  - 90
4099  - http://www.ajsonline.org/content/s3-15/90/423.short
4100  - http://www.ajsonline.org/content/s3-15/90/423.full
SO  - Am J Sci1878 Jun 01; s3-15