Number | Name | Date | Kind |
---|---|---|---|
2620580 | Dwinell | Dec 1952 | |
3013475 | Spangler | Dec 1961 | |
3131793 | Bohn | May 1964 | |
3345790 | Cornelissen | Oct 1967 | |
3863372 | Stilling | Feb 1975 |
Number | Date | Country |
---|---|---|
975921 | Oct 1975 | CAX |
Entry |
---|
Modern Plastics, vol. 28, issue 7, p. 62, 3-1951. |