Reading multifractal spectra: Aging by multifractal analysis of heart rateD. Makowiec, A. Rynkiewicz, R. Gała̧ska, J. Wdowczyk-Szulc and M. Żarczyńska-BuchowieckaEPL, 94 6 (2011) 68005DOI: https://doi.org/10.1209/0295-5075/94/68005