Eight women from the Martin family of Owosso, Michigan started singing as children and were directed by their father. They later studied voice as adults. In March of 1980 they made a record under the direction of Terri Corner and Ronald Davis as accompanist. Gregorian chant is the sung prayer of the Church. The Gregorian Mass IX from the Vatican Graduale is designated to be sung on feast days honoring the Blessed Virgin Mary. The chants for the Mass have approximate compositional dates that range from the eleventh through the fourteenth centuries. The Credo used in this recording is Credo III. C. Foeppel's 'Mass in Honor of the Holy Guardian Angel' is a two-part arrangement for soprano and alto with organ accompaniment. The edition was approved around the turn of the century by the Cincinnati Diocesan Commission of Church Music. Since for this Mass Foeppel did not include a musical setting for the Benedictus and Agnus Dei, compositions based on these tests by J. Wiegand were chosen for this recording.