Declaring XML namespaces for MathML

On this page of my site: http://ift.tt/XBTWjF

I have some code that looks like:

        <mml:math xmlns:mml="http://ift.tt/M2cV0i" overflow="scroll">

            <mml:mfenced open="(" close=")">
                <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                <mml:mi mathvariant="italic">s</mml:mi>
                </mml:msub>
                <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                <mml:mi mathvariant="italic">s</mml:mi>
                </mml:msub>
                <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                <mml:mi mathvariant="italic">s</mml:mi>
                </mml:msub>
                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                <mml:mi mathvariant="italic">s</mml:mi>
                </mml:msub>
            </mml:mfenced>
        </mml:math>

and in other places it looks like:

                    <math overflow="scroll">

                        <mrow>
                            <mi mathvariant="italic">Rr</mi>
                            <mo>=</mo>
                            <mrow>
                                <msub><mi mathvariant="italic">R</mi>
                                <mi mathvariant="italic">s</mi>
                                </msub>
                                <mo>⁢</mo>
                                <msub><mi mathvariant="italic">s</mi>
                                <mi mathvariant="italic">R</mi>
                                </msub>
                                <mo>+</mo>
                                <msub><mi mathvariant="italic">R</mi>
                                <mi mathvariant="italic">d</mi>
                                </msub>
                                <mo>⁢</mo>
                                <msub><mi mathvariant="italic">d</mi>
                                <mi mathvariant="italic">R</mi>
                                </msub>
                            </mrow>
                        </mrow>
                    </math>

The MathML markup in the places with the namespace prefix don't work, but the ones without the prefix seem to work just fine.

I could do a find and replace and remove the mml in all of my files, but I have hundreds of files and I would prefer to fix it if I can by editing my single shared header file. Is this possible?