...blazars

Figures 9, 11, 13, 20, 23, 26, 27, and 33 appear only in the electronic version of A&A on WWW at http://ed-phys.fr. Tables 4-48 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

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...Scaltriti

Visiting Astronomer, Complejo Astronómico El Leoncito operated under agreement between the Consejo Nacional de Investigaciones Cientificas y Técnicas de la República Argentina and the National Universities of La Plata, Córdoba and San Juan

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