In addition to his role in creating this first English language Mass, Dennis had a large stake in F.E.L. (Friends of the English Liturgy). Many of the contemporary artists who authored the folk music that was used in American Catholic Liturgy choose F.E.L. to be their publisher, as did Ray Repp, who pioneered contemporary Catholic liturgical music and authored the "First Mass for Young Americans," a suite of folk-style musical pieces designed for the Catholic liturgy. Repp gave an impetus to the development of "guitar masses."