namespace lyx {
+class HtmlStream;
class NormalStream;
class MapleStream;
class MaximaStream;
class MathData;
void write(MathData const &, WriteStream &);
+void htmlize(MathData const &, HtmlStream &);
void normalize(MathData const &, NormalStream &);
void maple(MathData const &, MapleStream &);
void maxima(MathData const &, MaximaStream &);