An intercessory prayer, sometimes called a memorial, addressed to a saint. A suffrage is preceded by an antiphon, a versicle, and a response, and may occur during the Divine Office. Suffrages of saints are often included in Books of Hours, where they are presented according to a hierarchy, beginning with the Trinity and often followed by the Virgin, Saint Michael, Saint John the Baptist, the apostles, martyrs, confessors, and female saints. The particular saints appearing in a group of suffrages vary according to region or personal devotions. Suffrages are known to have existed from at least the eleventh century (although the earliest extant manuscripts date from the thirteenth century).