| 其他書名 | A Comparison of the Earnings of Former Vocational Students Now Farming with the Earnings of an Equivalent Group in Farming who Did Not Receive Vocational Training. June 1933 |
| 出版 | U.S. Government Printing Office, 1932 |
| URL | http://books.google.com.hk/books?id=prB9uwEACAAJ&hl=&source=gbs_api |