This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Franciscus Aguilonius color scheme. en The RYB color scheme of Franciscus Aguilonius Francisci Agvilonii with primaries yellow flavus red rubeus and blue caeruleus arranged between white albus and black niger with orange aureus green viridis and purple purpureus as combinations of two primaries google id YBDAAAAcAAJ pg PA onepage