<<< native [ EUnderover False (EUnderover False (EIdentifier "BASE") (EIdentifier "first under script") (EIdentifier "second overscript")) (EIdentifier "second one") (EIdentifier "first overscript") , ESymbol Rel "=" , EUnderover False (EOver False (EUnder False (EIdentifier "BASE") (EIdentifier "first under script")) (EIdentifier "second overscript")) (EIdentifier "second one") (EIdentifier "first overscript") ] >>> mml $$\underset{\mathrm{second\; one}}{\overset{\mathrm{first\; overscript}}{\underset{\mathrm{first\; under\; script}}{\overset{\mathrm{second\; overscript}}{\mathrm{BASE}}}}}=\underset{\mathrm{second\; one}}{\overset{\mathrm{first\; overscript}}{\stackrel{\mathrm{second\; overscript}}{\underset{\mathrm{first\; under\; script}}{\mathrm{BASE}}}}}$$