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|---|---|---|---|
| 3333678 | Rodman | Aug 1967 | A |
| 3595380 | Miller | Jul 1971 | A |
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| 4153152 | Lapeyre | May 1979 | A |
| 4688670 | Lapeyre | Aug 1987 | A |
| 4742907 | Palmaer | May 1988 | A |
| 4754872 | Damkjaer | Jul 1988 | A |
| 5027944 | Damkjaer | Jul 1991 | A |
| 5307923 | Damkjaer | May 1994 | A |
| 5372248 | Horton | Dec 1994 | A |
| 5404997 | Schreier et al. | Apr 1995 | A |
| 5797820 | Endo | Aug 1998 | A |
| 5909797 | Van Den Goor | Jun 1999 | A |
| 5921379 | Horton | Jul 1999 | A |
| 6142295 | Greve | Nov 2000 | A |
| 6223889 | Layne et al. | May 2001 | B1 |
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| 6471048 | Thompson, Jr. et al. | Oct 2002 | B1 |
| 20010050214 | Guldenfels | Dec 2001 | A1 |
| Number | Date | Country |
|---|---|---|
| 7502105 | Feb 1975 | NL |
| Entry |
|---|
| ISA/EP International Search Report, PCT/US03/02573, completed Apr. 29, 2003 (mailed May 9, 2003). |