2440 20160701171705.0 ASTROimport-597 Verschueren, W. 1991 Towards accurate radial velocities from early type spectra in the framework of an ESO key programme In order to elucidate the internal kinematics in very young stellar groups, a dedicated machinery was set up, which made it possible to proceed from actual observations to reductions and correlation analysis to the ultimate derivation of early-type stellar radial velocities (RVs) with the requisite precision. The following ingredients are found to be essential to obtain RVs of early-type stars at the 1-km/s level of precision: high-resolution, high-S/N spectra covering a large wavelength range; maximal reduction of observational errors and the use of optimal reduction procedures; the intelligent use of a versatile cross-correlation package; and comparison of velocities derived from different regions of the spectrum in order to detect systematic mismatches between object and template spectrum in some of the lines. David, M. Hensberge, H. Memorie della Societa Astronomica Italiana 62 1991 953-958 http://esoads.eso.org/abs/1991MmSAI..62..953V published in NONREF