| Number | Date | Country | Kind |
|---|---|---|---|
| 61-165777 | Jul 1986 | JPX | |
| 61-166273 | Jul 1986 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 3648271 | McConnell et al. | Mar 1972 | |
| 4370645 | Carson et al. | Jan 1983 | |
| 4495491 | Postl | Jan 1985 | |
| 4648047 | Berkland et al. | Mar 1987 | |
| 4677571 | Riseman et al. | Jun 1987 |
| Number | Date | Country |
|---|---|---|
| 0066674 | Mar 1982 | EPX |
| Entry |
|---|
| IBM Technical Disclosure Bulletin, vol. 27, No. 11 Apr. 1985. |