One can hear it in almost all of his compositions. In his Requiem (1947) these ancient melodies are interwoven with the sound of the modern orchestra. At the beginning of the Introit, the choir sings the unaltered Gregorian melody. Listen to the chant: (mp3 – sourceChant – Music For Paradise. By: Cisterciënzer Monniken Van Stift Heiligenkreuz (Universal 4766774)Details: Amazon.com), and to the beginning of Duruflé’s Requiem: (mp3 – sourceFauré – Duruflé – Requiem. By: Richard Hickox (Eloquence 466 844-2)Details: Amazon.com)