Original source code (grappe 1.0) and algorithm:
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Gregory Kucherov <kucherov@loria.fr>, http://www.loria.fr/~kucherov/
Michael Rusinowitch <rusi@loria.fr>

First implementation of grappe 2.0:
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Eric Queffelec <queffelec@iie.cnam.fr>

New implementation of grappe (grappe 3.0) recoded from scratch:
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Sbastien Briais <sbriais@ens-lyon.fr>, http://www.ens-lyon.fr/~sbriais/