| Number | Date | Country | Kind |
|---|---|---|---|
| 4-361366 | Dec 1992 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2296346 | Hearn | Sep 1942 | |
| 3106436 | Weiss | Oct 1963 | |
| 3152853 | Scott | Oct 1964 | |
| 5145408 | Houtteman et al. | Jan 1992 | |
| 5281770 | Kamei et al. | Jan 1994 |
| Number | Date | Country |
|---|---|---|
| 0326141 | Jan 1989 | EPX |
| 0148878 | Jun 1990 | JPX |
| 0833639 | Dec 1956 | GBX |
| 1209158 | Dec 1967 | GBX |
| 2256541 | Aug 1992 | GBX |
| Entry |
|---|
| Western Electric Technical Digest No. 12 by R. E. Hotze & J. B. Krepp pp. 15 & 16, Oct. 1968. |