Analysis of information sources in references of the Wikipedia article "Thailand–United States relations" in English language version.
Both original letters still exist today in archives.
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1833. Convention of amity and commerce. concluded March 30, 1833; ratification advised by the Senate June 30, 1834; ratified by the President; ratifications exchanged April 14, 1836; proclaimed June 24, 1837. (Treaties and conventions, 1889. p. 992.) (The provisions of this treaty were modified by the Treaty of 1856.)
Archived by WebCite®
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Archived by WebCite®
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Both original letters still exist today in archives.
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