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      Introduction
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The aim of this package is to turn 
<Package> GAP </Package> more user-friendly, at least for semigroup theorists.
It requires the usage of external programs as is the case of 
<C>graphviz</C> <Cite Key="KoutsofiosNorth:2002"/>, a software for drawing graphs developed at AT
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    T Labs, that can be obtained at
    <URL>http://www.graphviz.org/</URL>.
It is used not only to draw right Cayley graphs of finite semigroups and Sch{\"u}zenberger graphs of finite inverse semigroups but also to visualize in the usual way the egg-box picture of a D-classe of a finite semigroup. 

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<B>Important note</B>: The version of <C>graphviz</C> to install should be
greater or equal to 1.16.
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Tcl/Tk should also be available in order to run the graphical interfaces
(XAutomaton and XSemigroup)
used to specify automata and semigroups.

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