Formulas encoding: example

    <OMOBJ xmlns="http://www.openmath.org/OpenMath">
      <OMA>
        <OMS cd="elementary" name="ordered-triple" />
        <OMV name="M" />
        <OMS cd="c6s1p4_Th2" name="times" />
        <OMV name="e" />
      </OMA>
    </OMOBJ>

and somewhere else

    <theory id="elementary">
      <symbol id="ordered-triple">
        <commonname>An ordered triple</commonname>
      </symbol>
    </theory>
    <presentation for="ordered-triple" theory="elementary">...</presentation>

<- ->