| Number | Name | Date | Kind |
|---|---|---|---|
| 3340096 | Mann et al. | Sep 1967 | |
| 4029518 | Matsutani et al. | Jun 1977 | |
| 4062102 | Lawrence et al. | Dec 1977 |
| Number | Date | Country |
|---|---|---|
| 1333593 | Oct 1973 | GBX |
| Entry |
|---|
| Ritter; E. S., "Recent Advances in Components of Space Power Systems", 1976, p. 141, Fig. 4. |