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| 3805474 | Gerstein | Apr 1974 | A |
| 3870292 | Bradley | Mar 1975 | A |
| 4163548 | Nystrand | Aug 1979 | A |
| 4190241 | Krueger | Feb 1980 | A |
| 4272066 | Bouda | Jun 1981 | A |
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| 4349185 | Small et al. | Sep 1982 | A |
| 4360194 | Bradley | Nov 1982 | A |
| 4521209 | DeFresne | Jun 1985 | A |
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| 4655739 | Pratt et al. | Apr 1987 | A |
| 4778441 | Couturier | Oct 1988 | A |
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| Number | Date | Country |
|---|---|---|
| 3227270 | Jan 1984 | DE |
| 19908169 | Sep 1999 | DE |
| 2679824 | May 1993 | FR |
| Entry |
|---|
| PCT Search Report dated Nov. 29, 2000. |