Cita APA (7a ed.)
Irvine, D. E. G., & Seshold, M. Errors in Postage Stamp Design.
Cita Chicago Style (17a ed.)
Irvine, David E. G., y Maxwell Seshold. Errors in Postage Stamp Design.
Cita MLA (9a ed.)
Irvine, David E. G., y Maxwell Seshold. Errors in Postage Stamp Design.
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