Stall speed
Good evening. All stall speeds are published as IAS, as this is the only way, for the pilot, to have a single reference speed at different altitude.
Correction tables correct then IAS to CAS. Clearly IAS should be free from instrument error - in flight test this is called TIAS, for True Indicated AirSpeed, where a perfect pitot tube feeds pressure to a perfect anemometer.
Cheers
Daniel