found: Rüfer, P. Drei Stücke für Violine und Orgel op. 36, 1989:t.p. (Philipp Rüfer) cover (Ph. Rüfer) p. 2 (Philipp Bartholomé Rüfer; b. June 7, 1844, Liège, d. Sept. 15, 1919, Berlin)
found: Rüfer, P. Sonate für die Orgel, op. 16, 187-?:t.p. (Ph. Rüfer)
found: Baker, 8th ed.(Rüfer, Philippe (-Barthélemy) [sic]; b. June 7, 1844, Liège, d. Sept. 15, 1919, Berlin; German pianist, teacher, and composer)
found: OCLC database, Oct. 3, 1997(hdgs.: Rüfer, Philippe, 1844-1919; Rüfer, Philippe Bartholomé, 1844- ; usage: Philipp Rüfer, Ph. Rüfer)
found: NYPL. Dict. cat. of the mus. coll.(hdg.: Ruefer, Philippe Bartholomé, 1844-1919; usage: Philipp Rüfer, Ph. Rüfer)
found: MGG:index (Rüfer, Philippe Bartholomé)
found: Rüfer, Philipp. Trio für Pianoforte, Violine und Violoncello, B-Dur, op. 34, 2017:cover (Philippe Bartholomé Rüfer) preliminary page iii (pianist, organist, composer, piano and score reading teacher)