Powell, W. F. (2006). Color mixing recipes for portraits: Featuring oil and acrylic-- plus a special section for watercolor. Walter Foster Pub..
Lua i Stíl Chicago (17ú heag.)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.
Lua MLA (9ú heag.)Powell, William F. Color Mixing Recipes for Portraits: Featuring Oil and Acrylic-- Plus a Special Section for Watercolor. Walter Foster Pub., 2006.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.