Test of named mathsize attribute
<math xmlns="http://www.w3.org/1998/Math/MathML"> <mi mathsize="small">A</mi> <mo>+</mo> <mi mathsize="big">A</mi> <mo>+</mo> <mi mathsize="3ex">A</mi> <mo>+</mo> <mi>B</mi> </math>
Author: Design Science, Inc. (E. Cannon, E. Tabacman, R.Miner)