Our research was supported by the ANR grant (ANR-09-SSOC-010-GEOSCIENCE) and by the Labex « Structurations des Mondes Sociaux » grant (ANR-11-LABX-0066).
The data from Thomson Scientific (now Clarivate Analytics) have been retrieved in the frame of an agreement involving OST-HCERES and the research laboratory (UMR LISST).