| Number | Name | Date | Kind |
|---|---|---|---|
| 1190459 | LeMoine et al. | Jul 1916 | |
| 1454426 | Clements | May 1923 | |
| 3106394 | Gelbart | Oct 1963 | |
| 4142715 | Matsumoto | Mar 1979 | |
| 4223471 | Greenberg | Sep 1980 | |
| 4586280 | Dang | May 1986 | |
| 4817311 | Ong | Apr 1989 | |
| 4923429 | Lewis | May 1990 | |
| 5018288 | Yang | May 1991 | |
| 5131175 | Liu | Jul 1992 |
| Number | Date | Country |
|---|---|---|
| 575173 | Apr 1933 | DE2 |
| 3618952 | Dec 1987 | DEX |
| 1442243 | Dec 1988 | SUX |
| Entry |
|---|
| U. K. Search Report No. 9113145.8. |