| Number | Date | Country | Kind |
|---|---|---|---|
| 3-162622 | Jul 1991 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4652240 | Wackym | Mar 1987 | |
| 4877408 | Hartsfield | Oct 1989 | |
| 5002491 | Abrahamson et al. | Mar 1991 |
| Entry |
|---|
| Watanabe, et al. CAI Handbook, Fuji Techno-System, 1989, pp. 212-223 and 446-460. (Japanese) |