| Number | Name | Date | Kind |
|---|---|---|---|
| 2802713 | Olpin et al. | Aug 1957 | |
| 2802714 | Olpin et al. | Aug 1957 | |
| 2959461 | Murray | Nov 1960 | |
| 3503087 | Wolf et al. | Mar 1970 | |
| 3663262 | Cogan, Jr. | May 1972 | |
| 3819324 | Bino | Jun 1974 | |
| 4102644 | Hauser et al. | Jul 1978 | |
| 4141684 | Kuhn | Feb 1979 | |
| 4167510 | Brendle | Sep 1979 | |
| 4505944 | Turner | Mar 1985 | |
| 4640690 | Baumgartner et al. | Feb 1987 | |
| 4732570 | Baumgartner et al. | Mar 1988 | |
| 4877411 | Hines et al. | Oct 1989 | |
| 5108460 | Hines et al. | Apr 1992 |
| Entry |
|---|
| Martin Sherwood and Christine Sutton, "The Physical World," 22 (1991). |