Giovan Paolo Lomazzo, Treatise on the Art of Painting, Milan, 1584 (RV E.III.37)

Lomazzo, a friend of the pupil and heir of Leonardo's manuscripts, Francesco Melzi, came into contact with the writings of the Renaissance Master and repeatedly made reference to them in his writings. This is true also of his Treatise on Painting, which was first printed in Milan in 1584.
Lomazzo also owned writings on the art of Leonardo, and thanks to these he was able to cite a part of the famous Comparison (comparison between the arts written by Leonardo in which painting was concluded to be a superior art form), which was not included in the Vatican Codex Urbinate lat. 1270 (manuscript compiled after Leonardo's death by his pupil and heir, Francesco Melzi). Lomazzo acknowledges having borrowed his praise of the plastic arts from a part of Leonardo writings that have since been lost. As such, Lomazzo’s work is considered to have been one of the most important sources for the spreading of da Vinci’s precepts in the field of painting, sixty-seven years before the publication of the editio princeps.