We present the results of a long-term periodicity search in a sample of γ-ray blazars within a multiwavelength context. These blazars have been selected from...

We present coordinated multiwavelength observations of the bright, nearby BL Lacertae object Mrk 421 taken in 2013 January–March, involving GASP-WEBT, Swift...

Blazars present highly variable gamma-ray emission. This variability, which can range from a few minutes to several years, is also observed at other wavelengths...

We report a characterization of the multiband flux variability and correlations of the nearby (z = 0.031) blazar Markarian 421 (Mrk 421) using data from...

In an effort to locate the sites of emission at different frequencies and physical processes causing variability in blazar jets, we have obtained high time...

Results of a program of near-IR monitoring of a sample of blazars and miniblazars observed during 1990 and 1991 with the Carlos Sanchez Telescope, in Teide...

Multiband near-infrared images of 12 BL Lacertae objects were obtained with the 2.5 m telescope at the Las Campanas Observatory in order to determine the...

We present new spectroscopic data of the BL Lac RGB 2243 + 203, and its surroundings, obtained with the OSIRIS Multi Object Spectrograph (MOS) mounted in the...

Extragalactic very-high-energy (VHE; E > 100 GeV) sources are unique objects to study the most powerful particle accelerators in nature, as active galactic...