def build(self, builder):
        """Build XML by appending to builder"""

        params = dict(OID=self.oid, Name=self.name)

        if self.unit_dictionary_name:
            params["mdsol:UnitDictionaryName"] = self.unit_dictionary_name

        for suffix in ["A", "B", "C", "K"]:
            val = getattr(self, "constant_{0}".format(suffix.lower()))
            params["mdsol:Constant{0}".format(suffix)] = str(val)

        if self.standard_unit:
            params["mdsol:StandardUnit"] = "Yes"

        builder.start("MeasurementUnit", params)
        for child in self.symbols:
            child.build(builder)
        builder.end("MeasurementUnit")