DAH; Wierda, 157; the earliest edition is: Il Codice Magliabechiano by Anonimo Fiorentino, [digitized from a collection at Harvard University]; Frey, Karl, 1857–1917. Publication date 1892. archive.org.
books.google.com
Early Printed Books as Material Objects, Proceedings of the Conference Organized by the IFLA Rare Books and Manuscripts Section, Munich, 19–21 August 2009, Editors: Bettina Wagner, Marcia Reed, 2010, Walter de Gruyter, ISBN3110253240, 783110253245, google books
uni-heidelberg.de
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Zöllner, Frank, "Leonardo's Portrait of Lisa del Giocondo", p. 245, in Leonardo Da Vinci, Selected Scholarship: Leonardo's projects, c. 1500–1519, edited by Claire J. Farago, 1999, Taylor & Francis, ISBN0815329350, 9780815329350; also Gazette des Beaux-Arts, 121 (1993), S. 1., PDF