Robertson, S., & Bertling, T. How to draw: Drawing and sketching objects and environments from your imagination.
Lua i Stíl Chicago (17ú heag.)Robertson, Scott, agus Thomas Bertling. How to Draw: Drawing and Sketching Objects and Environments from Your Imagination.
Lua MLA (8ú heag.)Robertson, Scott, agus Thomas Bertling. How to Draw: Drawing and Sketching Objects and Environments from Your Imagination.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.