PiCTeX is a set of macros by Michael Wichura for drawing diagrams and pictures. The macros are freely available; however, the PiCTeX manual itself is not free. Unfortunately, TUG is no longer able to supply copies of the manual (as it once did), and it is now available only through Personal TeX Inc, the vendors of PCTeX (http://www.pctex.com/). The manual is not available electronically.
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