Michael P. Salisbury and Sean E. Anderson and Ronen Barzel and David H. Salesin.
Interactive Pen-and-Ink Illustration.
In Computer Graphics, Proceedings of ACM SIGGRAPH 1994, pp. 101--108, 1994.

Bibtex:

@InProceedings{ salisbury:1994:IPII,
  author = 	"Michael P. Salisbury and Sean E. Anderson and Ronen
                 Barzel and David H. Salesin ",
  title = 	"Interactive Pen-and-Ink Illustration",
  booktitle = 	"Computer Graphics, Proceedings of ACM SIGGRAPH 1994",
  pages = 	"101--108",
  year = 	"1994",
}

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