| 其他書名 | To which is Appended a Special Report on the Correlation of the Coal Measures of Western Pennsylvania and Eastern Ohio |
| 出版 | Board of Commissioners, 1879 |
| URL | http://books.google.com.hk/books?id=7iye1anKdAAC&hl=&source=gbs_api |
| EBook | FULL_PUBLIC_DOMAIN |