<?xml version="1.0" encoding="UTF-8"?>

<math xmlns="http://www.w3.org/1998/Math/MathML" display="block">  <munderover>    <mi mathvariant="normal">BASE</mi>     <mi mathvariant="normal">under</mi>     <mi mathvariant="normal">over</mi>   </munderover>   <mo>=</mo>   <mover>    <mrow>      <munder>        <mi mathvariant="normal">BASE</mi>         <mi mathvariant="normal">under</mi>       </munder>     </mrow>     <mi mathvariant="normal">over</mi>   </mover> </math>