Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4816904 | Television and market research data collection system and method | William J. McKenna, Kenneth W. Silvers, Russell J. Welsh, Harold R. Walker, Joseph A. Cullity +1 more | 1989-03-28 |