Blazars (also known as BL Lac objects), first discovered in 1978, are unusually energetic objects in the extragalactic universe. About 200 are known or suspecte

Gamma ray astronomy, the branch of high energy astrophysics that studies the sky in energetic ?-ray photons, is destined to play a crucial role in the explorati

This volume gives a comprehensible survey of BL Lac objects: contributors summarize observations on these interesting astrophysical objects and present theoreti

This volume gives a comprehensible survey of BL Lac objects: contributors summarize observations on these interesting astrophysical objects and present theoreti