↑Franzen, C (December 2008). "Syphilis in composers and musicians--Mozart, Beethoven, Paganini, Schubert, Schumann, Smetana". European Journal of Clinical Microbiology and Infectious Diseases. 27 (12): 1151–7. doi:10.1007/s10096-008-0571-x. PMID18592279.