| Number | Name | Date | Kind |
|---|---|---|---|
| 4009884 | Weigl | Mar 1977 | A |
| 4248434 | Weigl | Feb 1981 | A |
| 4900027 | Sheridan | Feb 1990 | A |
| 4961581 | Barnes et al. | Oct 1990 | A |
| 5213334 | Yih | May 1993 | A |
| 5549301 | Gerrard | Aug 1996 | A |
| 5944314 | Stavinsky | Aug 1999 | A |
| 5954334 | Parker, Jr. | Sep 1999 | A |
| 6003870 | Johnson | Dec 1999 | A |
| 6059291 | Gary | May 2000 | A |
| 6155567 | Keleher | Dec 2000 | A |
| 6220597 | Scibetta | Apr 2001 | B1 |
| RE37957 | Garfield | Jan 2003 |
| Number | Date | Country |
|---|---|---|
| WO 9305855 | Apr 1993 | WO |
| Entry |
|---|
| McLeod, John: Toepen, http://www.pagat.com/last/toepen.html.* |
| McLeod, John: Spades, http://www.pagat.com/boston/spades.html.* |
| Morehead et al.: The New Complete Hoyle Revisd, 1991, Doubleday, p. 129-159. |