of Bianca Maria Sforza showing a similar hairstyle (National Gallery of Art) which has been suggested as being similar to one of Leonardo's. (Biblioteka Narodowa) in
Warsaw The first study of the drawing was published by Cristina Geddo. Geddo attributes this work to Leonardo based not only on stylistic considerations, extremely high quality and left-handed
hatching, but also on the evidence of the combination of black, white and red chalks (the
trois crayons technique). Leonardo was the first artist in Italy to use pastels, a drawing technique he had learned from the French artist
Jean Perréal, whom he met in Milan in 1494 and/or 1499. Leonardo acknowledges his debt to Perréal in the
Codex Atlanticus. Geddo also points out that the "coazzone" of the sitter's hairstyle was fashionable during the same period. Strong support for the attribution has come from Elizabetta Gnignera, the costume historian, in her book
La Bella Svelata, which studies a wide range of comparative costumes and hair styles.
Expert opinions A number of Leonardo experts and art historians have concurred with the attribution to Leonardo, including: • Martin Kemp, Emeritus Research Professor in the History of Art at the
University of Oxford, • Nicholas Turner, former curator at the British Museum and the J. Paul Getty Museum • Cristina Geddo, an expert on Milanese Leonardesques and
Giampietrino,
Analysis In 2010, after a two-year study of the picture, Kemp published his findings and conclusions in a book,
La Bella Principessa: The Story of the New Masterpiece by Leonardo da Vinci. The physical and scientific evidence from multispectral analysis and study of the painting, as described by Kemp in the first edition of his book with Cotte, This is a printed book with hand-illuminated additions containing a long propagandistic poem in praise of the father of Ludovico Sforza, who was Leonardo's patron, recounting the career. The Warsaw copy, printed on vellum with added illumination, was given to Galeazzo Sanseverino, a military commander under Ludovico Sforza, on his marriage to Bianca Sforza in 1496. According to Kemp and Cotte, the association with the
Sforziada suggests that the drawing is a portrait of Bianca Sforza, who was the daughter of Ludovico Sforza and his mistress Bernardina de Corradis. At the time of the portrait, she was around thirteen years old. Leonardo painted three other portraits associated with the family or court of Ludovico Sforza. The Polish scholar Bogdan Horodyski in 1954-1956 reached the conclusion that the Warsaw illumination refers to both the deceased dukes Galeazzo Maria and Gian Galeazzo and to the dynastic downfall after the usurpation of Ludovico il Moro. The reproduction of the unpublished heraldic figure attributed to Antonio Grifo, illuminated in the incunabulum "Comedia" by Dante (Cremonese, Venice 1491), now at Casa di Dante in Rome, shows the original coat of arms and insignia of the family of Galeazzo Sanseverino, and the comparison with those illuminated by Birago is not corresponding. Developing this hypothesis, Carla Glori suggests that Caterina Sforza, the daughter of Galeazzo Maria and half-sister of Gian Galeazzo, was the owner of the Warsaw Sforziad and that she gave it to the family of her deceased half-brother between 1496 and 1499. Horodyski's ideas have recently been revived by Katarzyna Krzyzagórska-Pisarek in her "
La Bella Principessa. Arguments against the Attribution to Leonardo",
Artibus et Historiae, XXXVI, 215, pp. 61– 89. Pisarek is a member of Artwatch UK, which has offered polemic denunciations of Kemp. ==Opposition to Leonardo attribution==