Number | Name | Date | Kind |
---|---|---|---|
2724159 | Morin | Nov 1955 | |
3155293 | Cotter | Nov 1964 | |
4224882 | Cruse | Sep 1980 | |
4388878 | Demzin | Jun 1983 | |
4520742 | Anderson | Jun 1985 | |
4824270 | Clarke | Apr 1989 | |
4915258 | Olson | Apr 1990 | |
5033398 | Froc | Jul 1991 | |
5092255 | Long et al. | Mar 1992 | |
5271343 | House | Dec 1993 |
Entry |
---|
Vacumeter Article, p. 12. |