Variable stars in the globular cluster M 28 (NGC 6626) G. Prieto, M. Catelan, R. Contreras Ramos, B. J. Pritzl, H. A. Smith and J. Alonso-García A&A, 543 (2012) A148 Published online: 13 July 2012 DOI: 10.1051/0004-6361/201118523