The variable cyclotron line in GX 301-2I. Kreykenbohm, J. Wilms, W. Coburn, M. Kuster, R. E. Rothschild, W. A. Heindl, P. Kretschmar and R. StaubertA&A, 427 3 (2004) 975-986DOI: https://doi.org/10.1051/0004-6361:20035836
