Robertson, S., & Bertling, T. How to draw: Drawing and sketching objects and environments from your imagination.
Chicago-viite (17. p.)Robertson, Scott, ja Thomas Bertling. How to Draw: Drawing and Sketching Objects and Environments from Your Imagination.
MLA-viite (8. p.)Robertson, Scott, ja Thomas Bertling. How to Draw: Drawing and Sketching Objects and Environments from Your Imagination.
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