美國郵票The Nineteenth Century Postage Stamps of the United States (Lindquist, 1947). John N. Luff and Benno Loewy, The Postage Stamps of the United States (New
美國駐英國大使美國駐英國大使(英語:United States Ambassador to the United Kingdom),正式名稱為美利堅合眾國駐聖詹姆斯朝廷大使(英語:The Ambassador of the United States of America to the Court of St
美国纸质辅币ISBN 978-0-87184-519-1. Knox, John Jay. United States Notes: A history of the various issues of paper money by the government of the United States 3rd. Charles Scribner’s
愛 (雕塑)(Washington, D.C.: United States Postal Service). 1972-12-21, (20904): 3 [2018-05-12]. (原始内容 (PDF)存档于2018-05-13). (3) Love (1973). Art of the Stamp. Smithsonian
南極條約郵票(PDF). Secretariat of the Antarctic Treaty: 2. 1968-11-29 [2022-10-03]. (原始内容存档 (PDF)于2022-07-01) (英语). Stamps : Wildlife Series. The Daily Courier. 1971-05-05: