Thomas Strothotte and Stefan Schlechtweg.
Non-Photorealistic Computer Graphics. Modelling, Animation, and Rendering.
Morgan Kaufmann, 2002.

Bibtex:

@Book{ 	         strothotte:2002:NPCG,
  author = 	 "Thomas Strothotte and Stefan Schlechtweg",
  title = 	 "Non-Photorealistic Computer Graphics. Modelling,
                  Animation, and Rendering",
  publisher = 	 "Morgan Kaufmann",
  year = 	 "2002",
}

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