In 1893 he published Theory of functions of a complex variable which had such an impact at Cambridge that function theory dominated there for many years. Whittaker writes in that this text:
Sa 1893 siya nai-publish na teorya ng pag-andar ng isang komplikadong variable na may ganitong epekto sa Cambridge na function theory duminado doon para sa maraming taon. Whittaker magsusulat sa text na ito: