| 其他書名 | Representing Aeronautics Branch, Department of Commerce, American Engineering Council, American Road Builders' Association, December 1, 1931 |
| 出版 | U.S. Government Printing Office, 1932 |
| URL | http://books.google.com.hk/books?id=6gpNAAAAMAAJ&hl=&source=gbs_api |
| EBook | FULL_PUBLIC_DOMAIN |