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        <h3><a href="../../../index.htm"><img alt="C++ Boost" src=
        "../../../boost.png" border="0" width="277" height="86"></a></h3>
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      <td valign="top">
        <h1 align="center">The Boost Statechart Library</h1>

        <h2 align="center">Rationale</h2>
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  <dl class="index">
    <dt><a href="#Introduction">Introduction</a><