| Number | Date | Country | Kind |
|---|---|---|---|
| 2717090 | Apr 1977 | DEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 3900887 | Soga et al. | Aug 1975 | |
| 4018986 | Wilk | Apr 1977 | |
| 4028733 | Ulicki | Jun 1977 | |
| 4045815 | Griffith et al. | Aug 1977 |
| Entry |
|---|
| King, A Novel TV Add-On Data Communication System, 1/74, Journal of the SMPTE, vol. 83, pp. 10-13. |