| Number | Name | Date | Kind |
|---|---|---|---|
| 4586716 | Brejcha et al. | May 1986 | |
| 4836556 | DeVale et al. | Jun 1989 | |
| 5482291 | Houriet, Jr. et al. | Jan 1996 | |
| 5626344 | Huang | May 1997 | |
| 5718433 | Lu et al. | Feb 1998 |
| Number | Date | Country |
|---|---|---|
| 2014321 | Aug 1996 | GBX |
| Entry |
|---|
| French Bulletin Des Bessins et Models Internationaux--Aug. 1994. |
| Harrows Ltd. Product Profile titled Quadro 240--1992. |