Johnston, B. (2003). The complete guide to coloured pencil techniques. David & Charles.
Chicago Style aipamenaJohnston, Beverley. The Complete Guide to Coloured Pencil Techniques. Brunel House, [Eng.]: David & Charles, 2003.
MLA aipamenaJohnston, Beverley. The Complete Guide to Coloured Pencil Techniques. David & Charles, 2003.
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