found: Grove book of opera singers, 2008:page 378 (Perron [Pergamenter], Karl; born Frankenthal, Pfalz, June 3, 1858; died Dresden, July 15, 1928; German bass-baritone; début in 1884 Leipzig as Wolfram; moved to Dresden in 1892; created roles: John the Baptist in Salome (1905), Orestes in Elektra (1909), and Ochs in Der Rosenkavalier (1911))
found: International who's who in music and musical gazetteer, 1918:page 486 (Perron, Karl; born Frankenthal, January 3, 1858; singer (high baritone); joined the Royal Opera, Dresden, 1891-1893; address Kgl. Hofoper, Dresden, Germany)
found: Concise Oxford dictionary of opera, 1996:page 395 (Perron, Karl; born Frankenthal, June 3, 1858; died Dresden, July 15, 1928; German baritone; studied Berlin with Hey and in Frankfurt with Stockhausen; in Leipzig until 1891; Dresden 1892-1894; Bayreuth 1889-1904)
found: Wikipedia, viewed on June 1, 2018(Karl Perron; born Karl Pergamenter; also known as Carl Perron; born Frankenthal, June 3, 1858; died Dresden, July 15, 1928; German bass-baritone; Kammersänger of the Dresden State Opera)