Number | Name | Date | Kind |
---|---|---|---|
2069134 | Collins et al. | Jan 1937 | |
2613931 | Singer | Oct 1952 | |
3253365 | Calderon | May 1966 | |
3551709 | Kemenczky | Dec 1970 | |
3841637 | Piazza | Oct 1974 |
Number | Date | Country |
---|---|---|
841,259 | Jun 1952 | DT |
1,009,079 | May 1957 | DT |
1,040,952 | Oct 1958 | DT |
Entry |
---|
Cenco 1969 Educational Catalog, p. 114, Solar Energy Demonstration Kit. |