Energy scaling of the “heartbeat” pulse width of GRS 1915+105, IGR J17091−3624, and MXB 1730−335 from Rossi-XTE observationsA. Maselli, F. Capitanio, M. Feroci, F. Massa, E. Massaro and T. MineoA&A, 612 (2018) A33DOI: https://doi.org/10.1051/0004-6361/201732097