About the Authors

Lutz Bornmann

bornmann@gv.mpg.de

Affiliation Division for Science and Innovation Studies, Administrative Headquarters of the Max Planck Society, Munich, Germany

Loet Leydesdorff

Affiliation Amsterdam School of Communication Research (ASCoR), University of Amsterdam, Amsterdam, The Netherlands

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: LB. Performed the experiments: LB. Analyzed the data: LB. Contributed reagents/materials/analysis tools: LB. Wrote the paper: LL.