| Number | Date | Country | Kind |
|---|---|---|---|
| 2001-173728 | Jun 2001 | JP |
| Number | Name | Date | Kind |
|---|---|---|---|
| 3336339 | England | Aug 1967 | A |
| 3825599 | England | Jul 1974 | A |
| 6215016 | Kawai et al. | Apr 2001 | B1 |
| Number | Date | Country |
|---|---|---|
| 238048 | Aug 1986 | DE |
| 1258033 | May 1969 | GB |
| 51-19126 | Feb 1976 | JP |
| Entry |
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