オットー・ジンガー
↑ Pratt, Waldo Selden, ed. (1920), “Singer, Otto”, Grove's Dictionary of Music and Musicians, 6 (American Supplement), New York: Macmillan Company, p. 362 .
↑ Universal Cyclopædia & Atlas, 1902, New York, D. Appleton & Co.
↑ 楽譜のクレジット表記等では多くの場合"Otto Singer"とのみ名乗った。
↑ Brainard's Biographies of American Musicians (edited by Elam D. Bomberger), p. 255
↑ http://vc.lib.harvard.edu/vc/deliver/~scores/009793895
↑ back cover of Otto Singer Jr.'s piano reduction of Das Liebesverbot, Breitkopf & Härtel, Leipzig, 1922