Atlas to the Coal Flora of Pennsylvania, and of the Carboniferous Formation Throughout the United States. Second Geological Survey of Pennsylvania : Report of Progress P. Harrisburg, Pennsylvania, Board of Commissioners for the Second Geological Survey 1879. Mit 87 dplblgr. lith. Taf. 18 S. Hldr. d. Zt. (Tls. beschabt u. best.). [...]
(Verschiedene Gebiete - Varia, Geologie - Mineralogie u. Paläontologie)