| 其他書名 | Papers Presented at the Annual Meeting of the ASA in New Orleans, Nov. 1968 |
| 出版 | American Society of Agronomy, Crop Sciens Society of America, Soil Science Society of America, 1969 |
| URL | http://books.google.com.hk/books?id=9Z7GmQEACAAJ&hl=&source=gbs_api |