| Number | Date | Country | Kind |
|---|---|---|---|
| 2138440 | Dec 1994 | CAX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 1280930 | Wolfe | Oct 1918 | |
| 2128749 | Koch et al. | Oct 1938 | |
| 2995374 | Deatherage | Aug 1961 | |
| 3016243 | Irwin | Jan 1962 | |
| 3798797 | Mandel | Mar 1974 | |
| 3805416 | Plefkey | Apr 1974 | |
| 4084816 | Shafer | Apr 1978 | |
| 4204343 | Brooks | May 1980 | |
| 4219197 | Acuff | Aug 1980 | |
| 4666163 | Hirschfeld | May 1987 | |
| 4944519 | Canela | Jul 1990 | |
| 5014996 | von Brauhut | May 1991 | |
| 5108113 | Leach | Apr 1992 | |
| 5195753 | Brukl et al. | Mar 1993 | |
| 5207435 | Tanner | May 1993 |
| Entry |
|---|
| "The Puzzle Mountain," Brandreth, G, (New York: Morrow and Company Inc) 1981, pp. 11, 106, 107, 113, 114. |