| 其他書名 | Wave lengths longer than 5500 A in the arc spectra of yttrium, lanthanum, and cerium. The preparation of pure rare earth elements |
| 出版 | U.S. Department of Commerce, Bureau of Standards, 1921 |
| URL | http://books.google.com.hk/books?id=LjEEuAPd6RsC&hl=&source=gbs_api |
| EBook | FULL_PUBLIC_DOMAIN |