Powell, W. F. (2006). Color mixing recipes for portraits: Featuring oil and acrylic-- plus a special section for watercolor. Walter Foster Pub..
Chicago-viite (17. p.)Powell, William F. Color Mixing Recipes for Portraits: Featuring Oil and Acrylic-- Plus a Special Section for Watercolor. Laguna Hills, CA: Walter Foster Pub., 2006.
MLA-viite (9. p.)Powell, William F. Color Mixing Recipes for Portraits: Featuring Oil and Acrylic-- Plus a Special Section for Watercolor. Walter Foster Pub., 2006.
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