Prince generates error message as "First aligngroup appears after other elements!" while using MathML mark-up "<maligngroup/>" in the XML file.
<math display="block" overflow="scroll" xmlns="http://www.w3.org/1998/Math/MathML" id="mth42" user-id="manual">
<mtable>
<mtr>
<mtd>
<maligngroup/>
<mi>D</mi>
<mfenced open="(" close=")">
<mi>λ</mi>
</mfenced>
<mo>=</mo>
<malignmark/>
<msup>
<msup>
<mi>λ</mi>
<mo>−</mo>
</msup>
<mn>1</mn>
</msup>
<mi>δ</mi>
<mfenced open="(" close=")">
<mrow>
<msup>
<msup>
<mi>λ</mi>
<mo>−</mo>
</msup>
<mn>1</mn>
</msup>
<mo>−</mo>
<msubsup>
<mi>λ</mi>
<mn>0</mn>
<mrow>
<mo>−</mo>
<mn>1</mn>
</mrow>
</msubsup>
</mrow>
</mfenced>
</mtd>
</mtr>
<mtr>
<mtd>
<maligngroup/>
<mo>=</mo>
<malignmark/>
<msub>
<mi>λ</mi>
<mn>0</mn>
</msub>
<mi>δ</mi>
<mfenced open="(" close=")">
<mrow>
<mi>λ</mi>
<mo>−</mo>
<msub>
<mi>λ</mi>
<mn>0</mn>
</msub>
</mrow>
</mfenced>
</mtd>
</mtr>
</mtable>
</math>
<math display="block" overflow="scroll" xmlns="http://www.w3.org/1998/Math/MathML" id="mth42" user-id="manual">
<mtable>
<mtr>
<mtd>
<maligngroup/>
<mi>D</mi>
<mfenced open="(" close=")">
<mi>λ</mi>
</mfenced>
<mo>=</mo>
<malignmark/>
<msup>
<msup>
<mi>λ</mi>
<mo>−</mo>
</msup>
<mn>1</mn>
</msup>
<mi>δ</mi>
<mfenced open="(" close=")">
<mrow>
<msup>
<msup>
<mi>λ</mi>
<mo>−</mo>
</msup>
<mn>1</mn>
</msup>
<mo>−</mo>
<msubsup>
<mi>λ</mi>
<mn>0</mn>
<mrow>
<mo>−</mo>
<mn>1</mn>
</mrow>
</msubsup>
</mrow>
</mfenced>
</mtd>
</mtr>
<mtr>
<mtd>
<maligngroup/>
<mo>=</mo>
<malignmark/>
<msub>
<mi>λ</mi>
<mn>0</mn>
</msub>
<mi>δ</mi>
<mfenced open="(" close=")">
<mrow>
<mi>λ</mi>
<mo>−</mo>
<msub>
<mi>λ</mi>
<mn>0</mn>
</msub>
</mrow>
</mfenced>
</mtd>
</mtr>
</mtable>
</math>