| 其他書名 | An Administrative Report of the Several Mineral Resource and General Geological Investigations Undertaken and Completed in Kentucky During the Biennial Period 1920-1921 |
| 出版 | Kentucky Geological Survey, 1921 |
| URL | http://books.google.com.hk/books?id=r2VCAQAAMAAJ&hl=&source=gbs_api |