Backbone of credit relationships in the Japanese credit marketLuca Marotta, Salvatore Miccichè, Yoshi Fujiwara, Hiroshi Iyetomi, Hideaki Aoyama, Mauro Gallegati and Rosario N MantegnaEPJ Data Sci., 5 1 (2016) 10DOI: https://doi.org/10.1140/epjds/s13688-016-0071-7