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As I recall, the Library of Congress was the initial source, but a few experts stepped in to provide additional information, one of whose notes can be found at http://commons.wikimedia.org/wiki/File_talk:Thomas_Rowlandson_-_Vaux-Hall_-_Dr._Johnson,_Oliver_Goldsmith,_Mary_Robinson,_et_al.jpg Adam Cuerden (talk) 11:31, 4 February 2013 (UTC)