The spectroscopic observations were conducted during several runs spanning 15 years from March 1988 to June 2003. The observations from the Southern Hemisphere were carried out in most cases at the European Southern Observatory (ESO, La Silla, Chile) with the 1.5m ESO telescope, equipped with a Boller & Chivens spectrograph. The first and last runs of observations were carried out at the 3.6m ESO telescope, located at the same site, using the ESO Faint Object Spectrograph and Camera EFOSC1 in the first run and EFOSC2 in the last one. The observations from the Northern Hemisphere were carried out at the 2.5m Isaac Newton Telescope at the Observatorio del Roque de los Muchachos (La Palma, Spain), using the IDS spectrograph, and at the 2.2m telescope at the Observatorio Hispano-Aleman (Calar Alto, Spain), also equipped with a Boller & Chivens spectrograph. (12 data files).