[A] The Principles of Harmony and Contrasts of Colours and their Application to the Arts. By M. E. Chevreul. Translated from the French by Charles Martel. Third Edition. London. George Bell and Sons. 1890.
[B] The Theory of Color in its relation to Art and Art Industry. By Dr. William Von Bezold. Translated from the German by S. K. Koehler with introduction and notes by Edward C. Pickering. Boston; L. Prang & Company, 1876.
[C] Tablets of paper instead of cardboard are recommended because in primary instruction the standards or types of color presented to the child ought to be the purest possible expressions of the colors represented, and a piece of color material cannot meet this requirement after having been used one year by a child. The necessary expense of cardboard tablets practically precludes a new supply each year. But the papers can finally be used to form, by pasting, some chart or combination which the pupil may be allowed to own as a sample of his work.
[D] A Nomenclature of Colors for Naturalists and Compendium of useful Knowledge for Ornithologists by Robert Ridgway, Curator, Department of Birds, National Museum. Boston, Little, Brown & Co., 1886.
