Absolute proper motions of 48 Hipparcos stars in nine elds distributed over the northern hemisphere are presented. The proper motions have been recently used as part of the Bonn program for the extragalactic link of the Hipparcos proper motion system. We describe methods which have led to the absolute proper motions of the major part of the Bonn elds for the link. For six elds the extra- galactic calibration was achieved using the bright quasar in the centre of the eld. In addition, data of three elds of globular clusters were included. For these elds the link to an extragalactic reference system was performed by stars, whose absolute proper motions with respect to galaxies were determined on plates of the Lick astrograph. In addition, we used for the link in one eld plates from the ESO Schmidt telescope in combination with measure- ments from glass copies of the Palomar Sky Survey. The accuracy of a single proper motion is of the order of 2 to 3 mas/a for each coordinate. 1