| Number | Name | Date | Kind |
|---|---|---|---|
| 4812839 | Okada et al. | Mar 1989 | |
| 4893336 | Wuthnow | Jan 1990 | |
| 5023868 | Davidson et al. | Jun 1991 | |
| 5029196 | Morganstein | Jul 1991 | |
| 5062103 | Davidson et al. | Oct 1991 | |
| 5065425 | Lecomte et al. | Nov 1991 |
| Entry |
|---|
| PC Magazine, Feb. 13, 1990, "Building Network Solutions: Is ISDN Tomorrow's Interoffice Network?", pp. 229-254. |