EUV waves are large-scale disturbances in the solar corona initiated by coronal mass ejections .
However , solar EUV images show only the wave fronts projections along the line-of-sight of the spacecraft .
We perform 3D reconstructions of EUV wave front heights using multi-point observations from STEREO-A and STEREO-B , and study their evolution to properly estimate the EUV wave kinematics .
We develop two different methods to solve the matching problem of the EUV wave crest on pairs of STEREO-A/-B images by combining epipolar geometry with the investigation of perturbation profiles .
The proposed approaches are applicable at the early and maximum stage of the event when STEREO-A/-B see different facets of the EUV wave , but also at the later stage when the wave front becomes diffusive and faint .
The techniques developed are demonstrated on two events observed at different separation of the STEREO spacecraft ( 42 ^ { \circ } and 91 ^ { \circ } ) .
For the 7 December 2007 event , we find that the emission of the EUV wave front mainly comes from a height range up to 90–104 Mm , decreasing later to 7–35 Mm .
Including the varying height of the EUV wave front allows us to correct the wave kinematics for the projection effects , resulting in velocities in the range 217–266 km/s .
For the 13 February 2009 event , the wave front height doubled from 54 to 93 Mm over 10 min , and the velocity derived is 205–208 km/s .
In the two events under study , the corrected speeds differ by up to 25 % from the uncorrected ones , depending on the wave front height evolution .