Butterfly Shareware for Windows CDROM CDROM, March 1996.  Walnut Creek CDROM.
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 Plotting related material
 path: \zipped\plot 
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digi138.zip  Digitize v1.38 x,y plot digitizer (scanned plot to x,y points)
splt220w.zip Splot v2.20 the pen plotter simulator (HP7475A) (good)