APA (7th ed.) Zitazioa
Scott Publishing Co, Snee, C., Kloetzel, J. E., & Houseman, D. Specialized Catalogue of United States Stamps and Covers: 2015 (Nonagésima tercera edición.).
Chicago Style (17th ed.) Zitazioa
Scott Publishing Co, Charles Snee, James E. Kloetzel, eta Donna Houseman. Specialized Catalogue of United States Stamps and Covers: 2015. Nonagésima tercera edición.
MLA (9th ed.) Zitazioa
Scott Publishing Co, et al. Specialized Catalogue of United States Stamps and Covers: 2015. Nonagésima tercera edición.
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