Number | Name | Date | Kind |
---|---|---|---|
1216840 | Ramsey et al. | Feb 1917 | |
2236926 | Surface | Apr 1941 | |
2839841 | Berry | Jun 1958 | |
3081089 | Gustafson | Mar 1963 | |
3289322 | Patrick | Dec 1966 | |
3645535 | Randolph | Feb 1972 | |
3655201 | Nichols | Apr 1972 | |
3659360 | Zeischegg | May 1972 | |
3953948 | Hogan | May 1976 | |
4014110 | Mayer | Mar 1977 | |
4238905 | MacGraw | Dec 1980 | |
4258479 | Roane | Mar 1981 | |
4317654 | Wahl | Mar 1982 |
Number | Date | Country |
---|---|---|
170062 | Dec 1977 | HUX |
55-3956 | Jan 1980 | JPX |
55-8192 | Mar 1980 | JPX |
55-8193 | Mar 1980 | JPX |
Entry |
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Patent & Trademark Office Inventor's Day handout illustrating polyhedrons, Feb. 7-8, 1976. |
Evercheering Enterprise Co., Ltd. advertisement, 6-19-81. |
Pyraminx.RTM. instruction sheet, copyright 1981. |