Positional reference stars in the Magellanic Clouds.

From a total of 27 multicolour plates obtained with the ESO Schmidt telescope in the direction of the Magellanic Clouds, we have determined the equatorial coordinates of 926 stars (mainly of galactic origin) at the mean epoch {TAU} = 1978.4 with an overall accuracy characterized by the mean values of the O-C quantities, S_a_=0.35" and S_d_=0.38", calculated from the coordinates of the Perth reference stars. These values are larger than the accuracy expected for primary standard stars; however they allow to consider the new positions as those of reliable secondary standard stars; the published positions correspond, in any case, to an unquestionable improvement of the quality of the coordinates provided in the current catalogues. This work represents an "astrometric step" in the starting of a "Durchmusterung" of the Magellanic Clouds organized by de Boer (1988,1989). Kev words: astrometry - Galaxies: Magellanic Clouds - reference systems.