Example exc-137

Prev: exc-136

Next: exc-138

xyz f xy

<math>
<apply><laplacian/>
<bvar><ci>x</ci></bvar><bvar><ci>y</ci></bvar><bvar><ci>z</ci></bvar>
  <apply><ci>f</ci>
    <ci>x</ci><ci>y</ci>
  </apply>
</apply>
</math>