| Number | Name | Date | Kind |
|---|---|---|---|
| 2844964 | Guibert | Jul 1958 | |
| 3566865 | Hay | Mar 1971 | |
| 3896673 | Audouze et al. | Jul 1975 | |
| 4307620 | Jiskoot | Dec 1981 | |
| 4413533 | Diesel | Nov 1983 | |
| 4674343 | Larson | Jun 1987 | |
| 4791821 | Spencer | Dec 1988 | |
| 4823623 | Carpenter et al. | Apr 1989 | |
| 4879915 | Spencer | Nov 1989 | |
| 4939940 | Tsukida | Jul 1990 | |
| 4986138 | Spencer | Jan 1991 | |
| 5003830 | Spencer | Apr 1991 | |
| 5029485 | Marr | Jul 1991 | |
| 5038623 | Zeh | Aug 1991 | |
| 5060529 | Bals et al. | Oct 1991 | |
| 5092988 | Womack et al. | Mar 1992 |
| Number | Date | Country |
|---|---|---|
| 0725235 | Sep 1942 | DE2 |
| 2918768 | Nov 1980 | DEX |
| 2343239 | Sep 1977 | FRX |
| 0868429 | Sep 1981 | SUX |
| Entry |
|---|
| Dopak, Inc. advertisements pp. 1-34. |