Ernest Willem [Ernest] Mulder (21/07/1898 - 12/04/1959), a Dutch composer and theorist, born in Amsterdam. He studied piano with Ulfert Schulz and composition with Bernard Zweers at the Amsterdam Conservatory. He was professor of composition and theory at the Amsterdam Conservatory. He wrote songs, choral compositions, the opera Dafne, 4 symphonies (among which two with choir and soloists), Requiem, Te Deum, Stabat Mater, incidental music for the medieval play Esmoreit and chamber music. Ars contrapunctica I and Ars contrapunctica II, as the titles implies, constitute a real anthology of contrapuntal technique. He wrote a book on harmony and a book on polyphony.