tendsto8

tendsto type = "two-sided" with <reln>

W3C sample	WIRIS
	$x^2\rightarrow a^2$

<math xmlns="http://www.w3.org/1998/Math/MathML">
  <reln>
    <tendsto type="two-sided"/>
    <apply>
      <power/>
      <ci>x</ci>
      <cn>2</cn>
    </apply>
    <apply>
      <power/>
      <ci>a</ci>
      <cn>2</cn>
    </apply>
  </reln>
</math>

Author: Design Science, Inc. (E. Cannon, E. Tabacman, R.Miner)