Schematron using XPath 2.0
//ebt:Reference_Frame_Identification/Rule
At least one of the following must be present: ebt:frame_spice_name, ebt:name, pds:Internal_Reference.
//ebt:Reference_Frame_Identification/pds:Internal_Reference/Rule
For Internal_Reference in ebt:Reference_Frame_Identification, reference_type must equal 'geometry_to_reference_frame'
ebt:Airmass/ebt:airmass/ebt:airmass
The attribute @unit must be equal to one of the following values 'airmass'.
ebt:Instrument_Parameters/ebt:instrument_temperature/ebt:instrument_temperature
The attribute @unit must be equal to one of the following values 'K', 'degC'.
ebt:Reference_Frame_Parameters/ebt:coordinate_system_celestial_pole_latitude/ebt:coordinate_system_celestial_pole_latitude
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Reference_Frame_Parameters/ebt:coordinate_system_celestial_pole_longitude/ebt:coordinate_system_celestial_pole_longitude
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Seeing/ebt:seeing_full_width_half_maximum/ebt:seeing_full_width_half_maximum
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Target_Geometry/ebt:solar_phase_angle/ebt:solar_phase_angle
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Target_Geometry/ebt:subobserver_latitude/ebt:subobserver_latitude
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Target_Geometry/ebt:subobserver_longitude/ebt:subobserver_longitude
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Target_Geometry/ebt:subsolar_latitude/ebt:subsolar_latitude
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Target_Geometry/ebt:subsolar_longitude/ebt:subsolar_longitude
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:Weather/ebt:ambient_pressure/ebt:ambient_pressure
The attribute @unit must be equal to one of the following values 'Pa', 'bar', 'hPa', 'mbar'.
ebt:Weather/ebt:ambient_temperature/ebt:ambient_temperature
The attribute @unit must be equal to one of the following values 'K', 'degC'.
ebt:World_Axis/ebt:coordinate_system_projection/ebt:coordinate_system_projection
The attribute ebt:World_Axis/ebt:coordinate_system_projection must be equal to one of the following values 'Gnomonic', 'Gnomonic plus SIP', 'Gnomonic with distortion term', 'Gnomonic with polynomial distortion', 'Gnomonic with polynomial distortion plus SIP', 'Hammer-Aitoff', 'Mercator', 'North Celestial Pole', 'Orthographic', 'Sanson-Flamsteed', 'Stereographic', 'Zenithal Equidistant', 'Zenithal with distortion term'.
ebt:World_Axis/ebt:horizontal_coordinate_pixel/ebt:horizontal_coordinate_pixel
The attribute @unit must be equal to one of the following values 'DN', 'W/m**2/sr/nm/(DN/s)', 'electron/DN', 'electrons', 'nm/mm', 'pixel'.
ebt:World_Axis/ebt:vertical_coordinate_pixel/ebt:vertical_coordinate_pixel
The attribute @unit must be equal to one of the following values 'DN', 'W/m**2/sr/nm/(DN/s)', 'electron/DN', 'electrons', 'nm/mm', 'pixel'.
ebt:World_Axis/ebt:world_coordinate_reference_point/ebt:world_coordinate_reference_point
The attribute @unit must be equal to one of the following values 'arcmin', 'arcsec', 'deg', 'hr', 'microrad', 'mrad', 'rad'.
ebt:World_Coordinate_System/Rule
If ebt:coordinate_system_projection includes polynomial distortion, you must use the ebt:PV_Distortion_Matrix class.
ebt:World_Coordinate_System/Rule
If ebt:coordinate_system_projection includes 'plus SIP', you must use the ebt:SIP_Distortion_Terms class.
ebt:World_Coordinate_System/ebt:Reference_Frame_Parameters/Rule
If ebt:Reference_Frame_Identification/ebt:name = GAPPT or ICRS, then ebt:coordinate_system_equinox must be nill.
ebt:World_Coordinate_System/ebt:Reference_Frame_Parameters/Rule
The number of ebt:World_Axis elements must match the number found in the ebt:wcs_axes attribute.