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HOME
Canada - 16 Slide Rule Patents
KEEP ISRM FREE!
Donations are
tax deductable
Work in Progress
- Clickable Thumbnails to PDF files will be added first followed by descriptions
1944 - 1952
CA457012A
CA458817A
CA465387
CA481293A
CA483693A
1952 -1958
CA484510A
CA489176A
CA515949A
CA531002A
CA532587A
1958 - Present
CA565467A
CA644977A
CA671991A
CA693696A
CA1083545A1
CA2156036A1
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