| 其他書名 | Proceedings of the Fifty-second Conference of the American Country Life Association, Inc. Education Center, University of Northern Iowa, Cedar Falls, Iowa, July 9-10, 1973 |
| 出版 | American Country Life Association, 1973 |
| URL | http://books.google.com.hk/books?id=FOABHAAACAAJ&hl=&source=gbs_api |