Bert Freudenberg and Maic Masuch and Thomas Strothotte.
Walk-Through Illustrations: Frame-Coherent Pen-and-Ink Style in a Game Engine.
In Computer Graphics Forum: Proceedings of Eurographics 2001, vol. 20, no. 3, pp. 184--191, 2001.

Bibtex:

@Article{ 	freudenberg:2001:WTIF,
  author = 	"Bert Freudenberg and Maic Masuch and Thomas
                 Strothotte",
  title = 	"Walk-Through Illustrations: Frame-Coherent
                 Pen-and-Ink Style in a Game Engine",
  journal = 	"Computer Graphics Forum: Proceedings of Eurographics
                 2001",
  volume = 	"20",
  number = 	"3",
  pages = 	"184--191",
  year = 	"2001",
}

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