Aharonian, F., Akhperjanian, A., Bazer-Bachi, A., Behera, B., Beilicke, M., Benbow, W., …Ward, M. (2008). Discovery of very high energy gamma-ray emission coincident with molecular clouds in the W 28 (G6.4-0.1) field. Astronomy and Astrophysics, 481(2), 401-410. https://doi.org/10.1051/0004-6361%3A20077765