found: His Anweisung zu der neuen clarinette, c1826.
found: His Symphonie concertante in E♭ op. 23 for two clarinets & piano, 1980:t.p. (Iwan Müller) pref. (Reval 1786-1854 Buckeburg) [info. from WU]
found: MGG,v. 9, col. 856 (Müller, Ivan)
found: His Six easy duets, c1957:cover (Mueller) caption (Ivan Mueller)
found: Acta Seminarii Philologici Erlangensis, v. 1:t.p. (Iwanus Mueller)
found: Grove music online, 23 September 2015(Müller, Iwan; born Reval (now Tallinn), Estonia, 3 December 1786; died Bückeburg, 4 February 1854; German clarinettist and basset-horn player; inventor; composer)