Abstract
We show here that recent ephemeris, accounting for the light curve of EN Lac in the 1980's cannot represent all the observations made at that time. Likely explanations can be: either rapid variations in the amplitude of the third (0.182d) period, or large imprecisions in the published amplitudes of the two first periods (0.169 and 0.171d). Thus, if we accept the periods previously determined, a serious doubt is raised against the amplitudes published previously.
