Schematron using XPath 2.0
The attribute msn:mission_phase_name must be equal to one of the following values 'ATLO', 'CRUISE', 'DEVELOPMENT', 'SURFACE MISSION', 'TEST'.
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'mrad', 'rad'.