Cen A
Narrabri: J. Grindlay et al., Astrophys. J., 197, L9 (1975)
Durham: Carraminana et al. Astron. Astrophys. 228, 327 (1990) [U.L.]
CANGAROO-I: G. Rowell et al., Astropart. Phys. 11, 217 (1999) [U.L.]
CANGAROO-III: S. Kabuki et al., Astrophys. J., 668, 968-973 (2007) [U.L.]
H.E.S.S.: F. Aharonian et al., Astron. Astrophys. 441 (2005) 465-472 [U.L.]
F. Aharonian
et al., Astrophys. J. 695 (2009) L40-L44
The H.E.S.S.
Collaboration, Nature 582 (2020) 356-359 [jet]