twodimensionaladdition1

W3C sample	WIRIS
	$$\mathrm{٣٢١}\mathrm{٦٥٤}+\mathrm{٩٧٥}$$

<math xmlns="http://www.w3.org/1998/Math/MathML" display="block" dir="rtl">
  <mstack>
    <msgroup>
      <mn>٣٢١</mn>
      <msrow>
        <mn>٦٥٤</mn>
        <mo>+</mo>
      </msrow>
    </msgroup>
    <msline/>
    <mn>٩٧٥</mn>
  </mstack>
</math>

Author: Abdelshafi Bekhit, school-book of elementary school for mathematics, Province Cairo of Egypt and the same in Arabic probably.