Olsen, H. (1963). Painting portraits: How to capture likeness and personality. Oak Tree Press.
Chicago-viite (17. p.)Olsen, Helen. Painting Portraits: How to Capture Likeness and Personality. London: Oak Tree Press, 1963.
MLA-viite (9. p.)Olsen, Helen. Painting Portraits: How to Capture Likeness and Personality. Oak Tree Press, 1963.
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