PS

 Projection     : Polar Stereographic
 General class  : azimuthal
 Characteristics: conformal
 Earth model    : ellipsoid or sphere

Defining the MAPUNITS:

 MapUnits "ps"       ! Standard name
 MapUnits "ps e0"    ! Standard name and ellipsoid

Other parameters:

 TrueOriginLongitude "central_meridian"        ! Required, for True origin
 TrueOriginLatitude  "latitude_of_true_scale"  ! Required, for True origin
 FalseEasting        "false_easting"           ! Optional, default is zero
 FalseNorthing       "false_northing"          ! Optional, default is zero