NGC 253
[References]
CANGAROO-II: Itoh, C. et al., Astronomy and Astrophysics 396, L1-L4
(2002),
Itoh, C. et al., Astronomy and
Astrophysics, 402, 443-455 (2003)
Erratum: Itoh, C. et al., Astron. Astrophys.
462, 67-71 (2007)
H.E.S.S.: Aharonian, F. et al., Astron. Astrophys. 442, 177-183 (2005) [upper limit]
D.Nedbal et al., 30th ICRC (2007) / arXiv:0710.4057 [astro-ph]
p.181 [upper limit]