Number | Name | Date | Kind |
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D285699 | Leopoldi | Sep 1986 | |
D311294 | Litowitz | Oct 1990 | |
D331681 | Schaefer et al. | Dec 1992 | |
D377287 | Biba | Jan 1997 | |
515155 | Nelson | Feb 1894 | |
2164206 | Gits et al. | Apr 1939 | |
5518057 | Huang | May 1996 | |
5542461 | Huang | Aug 1996 | |
5579819 | Hung et al. | Dec 1996 |