ath.org - a powerful math engine and math scripting language</a><br>
                 <a href="https://play.google.com/store/apps/details?id=org.mathparser.scalar.lite" target="_blank">Scalar Lite</a><br>
                 <a href="https://play.google.com/store/apps/details?id=org.mathparser.scalar.pro" target="_blank">Scalar Pro</a><br>
                 <a href="https://mathspace.pl" target="_blank">MathSpace.pl</a><br></dd>
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