| Number | Date | Country | Kind |
|---|---|---|---|
| 2001-004347 | Jan 2001 | JP |
| Number | Name | Date | Kind |
|---|---|---|---|
| 1455395 | Exum | May 1923 | A |
| 1943282 | Bellavia | Jan 1934 | A |
| 2260586 | Sheldon | Oct 1941 | A |
| 3353885 | Hanson | Nov 1967 | A |
| 5303057 | Davidow et al. | Apr 1994 | A |
| Number | Date | Country |
|---|---|---|
| 161 900 | Jul 1905 | DE |
| 644825 | Mar 1964 | FR |
| 2 155 123 | May 1973 | FR |
| WO 9415824 | Jul 1994 | WO |
| Entry |
|---|
| European Search Report dated Jun. 6, 2002. |