| Number | Name | Date | Kind |
|---|---|---|---|
| 2340881 | Kelley et al. | Feb 1944 | |
| 2541101 | Robinette et al. | Feb 1951 | |
| 2662834 | Paist et al. | Dec 1953 | |
| 3046297 | Overbeek et al. | Jul 1962 | |
| 3660582 | DiPietro et al. | May 1972 | |
| 3719547 | Martin et al. | Mar 1973 | |
| 3719597 | Wegerhoff et al. | Mar 1973 |
| Number | Date | Country |
|---|---|---|
| 1,534,719 | Aug 1968 | FR |
| Entry |
|---|
| Rayner, et al., Chemical Abstracts, Vol. 64: 16,1336, (1966). |
| Mayer, et al., Chemical Abstracts, Vol. 76: 60,868t (1972). |
| Barton et al., Chemical Abstracts, Vol. 76: 128,618u (1972). |