[1] Merrifield. 1844. A Treatise on Painting. Written by Cennino Cennini: p. 22. See also Broecke. 2015. Cennino Cennini’s Il libro dell’arte: p. 60-61. https://books.google.nl/books?id=O5VkAAAAcAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false.