Lady with a book of Petrarch's rhyme

The small book in her hands is a petrarchino, a pocket-sized printed edition of Petrarch's love poems, the kind a fashionable Florentine carried for private reading in the 16th century. Andrea has opened it to a real, identifiable page, two sonnets in which the poet sends his warm sighs to a cold, unmoved heart. She holds it out toward us with the ghost of a smile, as if inviting us to read along. Who she was is uncertain. Because her face turns up in several of Andrea's paintings, some believe she was Maria, the daughter of his wife Lucrezia from an earlier marriage. For a long time the picture was not even credited to him. An Uffizi inventory of 1589 listed it as a Pontormo, and only in 1634 was it returned to Andrea's name.