3C66A

[References]

Crimea: Y.I. Nashpor et al., Pis'ma Astron. Zh., 24, 167-171 (1998) [Astronomy Letters, 24, 134-138 (1998)]
           Neshpor, Yu. I. et al., Astronomy Report, 44, 641 (2000)
           Stepanian, A.A. et al., Astronomy Report, 46, 634 (2002)

HEGRA: F. Aharonian et al., A. & Ap., 353, 847 (2000) [upper limit]

Whipple: D. Horan et al., Ap. J. 603, 51 (2004) [upper limit]

STACEE: D.A. Bramel et al., Astrophys. J. 629, 108-114 (2005) [upper limit]

VERITAS: S. Swordy, ATel #1753 (Oct. 1, 2008)
              V. A. Acciari et al., arXiv:0901.4527 [astro-ph.HE]

MAGIC: E. Aliu et al., ApJ 692, 29-33 (2009)  [upper limit]