APA (7th ed.) Zitazioa
Mackay, J. D. The Complete Guide to Stamps and Stamp Collecting.
Chicago Style (17th ed.) Zitazioa
Mackay, James Dr. The Complete Guide to Stamps and Stamp Collecting.
MLA (9th ed.) Zitazioa
Mackay, James Dr. The Complete Guide to Stamps and Stamp Collecting.
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