All About Stamp Perforations
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Perforation
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April 5 Siegel auction features part 1 of Getlan collection of U.S. machine perforations
Perforation
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Identifier for US Washington/Franklin Stamps of 1908-1922
Perforation Measurement
Identifier for US Washington/Franklin Stamps of 1908-1922
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Perforation Measurement
What Are Stamp Perforations?
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Perforation
