@ARTICLE{10.21494/ISTE.OP.2020.0557, TITLE={From a simple drawing of Leonardo da Vinci to "first forms"}, AUTHOR={Jean-Pierre Crettez, }, JOURNAL={Art and Science}, VOLUME={4}, NUMBER={Issue 4}, YEAR={2020}, URL={https://openscience.fr/From-a-simple-drawing-of-Leonardo-da-Vinci-to-first-forms}, DOI={10.21494/ISTE.OP.2020.0557}, ISSN={2515-8767}, ABSTRACT={The geometric analysis of a drawing representing the profile of a man’s head gives us a glimpse of how Leonardo established his constructive approach to profiles from a first form. The geometric analysis of three other Leonardo profiles confirms this approach. It is with this same approach that Leonardo produced his five female portraits.}}