Welcome to Tetragon
(A square sort of person)
This web site is a random collection of the thoughts and ideas of one person, whom we will call Tetragon, an appropriate name for a square sort of person.
The ideas presented here are freely available for any purpose by any person or institution, provided that such use acknowledges this web site, tetragon.free.fr, as the source. Material may be reproduced in any form for any purpose, provided that the copyright notice (at bottom) is preserved.
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