On the history (15th-20th cs.) and usage of the liturgical manuscripts (mid-12th-early 16th cs.; Florence, various collections) from the church library of S. Maria del Fiore, Florence. Identifies 16 typologies among these manuscripts and examines their function in the context of the liturgy celebrated in the cathedral. (Notes that the cathedral collection also included many liturgical manuscripts that were not originally produced for the library). Observes that ca.40 manuscripts (14th-16th cs.) remained in the Opera dell'Duomo after the others were transferred (1778) to the Biblioteca medicea-laurenziana. ;