Question: Diagrams based off of this Seiss-German artist are known as what?
Sentence (from "Paul Klee"): Klee was a natural draftsman who experimented with and eventually deeply explored color theory, writing about it extensively; his lectures "Writings on Form and Design Theory" ("Schriften zur Form und Gestaltungslehre"), published in English as the "Paul Klee Notebooks", are held to be as important for modern art as Leonardo da Vinci's "A Treatise on Painting" for the Renaissance.
Relevant evidence: No