Issued Patents 1997
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D377949 | Digital/analog teaching clock | Richard Woldenberg, Tirza Ernst, Barbara Plain | 1997-02-11 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D377949 | Digital/analog teaching clock | Richard Woldenberg, Tirza Ernst, Barbara Plain | 1997-02-11 |