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   Xfig
   Xfig is a free and open source vector graphics editor which runs under the X Window System on most UNIX-compatible platforms. In Xfig, figures may be drawn using objects such as circles, boxes, lines, spline curves, text, etc. It is also possible to import images in formats such as GIF, JPEG, EPS, ...
   Found op http://en.wikipedia.org/wiki/Xfig
   
   

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