About the Authors

Matjaž Perc

matjaz.perc@uni-mb.si

Affiliation Faculty of Natural Sciences and Mathematics, University of Maribor, Slovenia

Zhen Wang

Affiliation School of Physics, Nankai University, Tianjin, China,

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

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