| Number | Name | Date | Kind |
|---|---|---|---|
| 2661768 | Novak et al. | Dec 1953 | |
| 3468563 | Duret | Sep 1969 | |
| 3480300 | Jeffrey et al. | Nov 1969 | |
| 3526417 | Aumiller | Apr 1968 | |
| 3881392 | Curtis | May 1975 | |
| 4046387 | Lee | Sep 1977 | |
| 4131050 | Holmes | Dec 1978 | |
| 4258943 | Vogt et al. | Mar 1981 | |
| 4293257 | Peterson | Oct 1981 | |
| 4572552 | Orevik et al. | Feb 1986 | |
| 4575130 | Pemberton et al. | Mar 1986 | |
| 4614120 | Fradin et al. | Sep 1986 | |
| 4618171 | Fahl | Oct 1986 | |
| 4659119 | Reimert | Apr 1987 | |
| 4703957 | Blenkush | Nov 1987 | |
| 4712810 | Pozzi | Dec 1987 |
| Number | Date | Country |
|---|---|---|
| 22568 | Jun 1948 | FIX |
| 1544720 | Sep 1968 | FRX |
| 8403927 | Oct 1984 | WOX |
| 215389 | Sep 1941 | CHX |
| 966842 | Aug 1964 | GBX |
| Entry |
|---|
| IBM Technical Disclosure Bulletin, vol. 17, No. 7, Dec. 1974. |