| Number | Name | Date | Kind |
|---|---|---|---|
| 1603592 | Glasner | Oct 1926 | |
| 3409347 | Vogel | Nov 1968 | |
| 3412493 | French | Nov 1968 | |
| 3694240 | Miller et al. | Sep 1972 | |
| 3781113 | Thomas | Dec 1973 |
| Entry |
|---|
| Schuenzel & Moore, "Credit Card System," IBM Technical Disclosure Bulletin, vol. 13, No. 1, Jun. 1970. |