Gasparrini, DarioDarioGasparrini2020-09-172020-09-172011-06-01https://hdl.handle.net/20.500.13025/2186The Astronomer's Telegram, #3462The Large Area Telescope (LAT), one of the instruments on board the Fermi Gamma-ray Space Telescope, has observed a significant change of the gamma-ray spectrum from a source positionally coincident with BL Lacertae.Gamma Ray>GeVAGNBlazarQuasarhttp://adsabs.harvard.edu/abs/2011ATel.3462....1G2011ATel.3462....1G