**Author details**

## López-Ruiz Ricardo

*Department of Computer Science, Faculty of Science, Universidad de Zaragoza, Zaragoza, Spain Also at BIFI, Institute for Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, Zaragoza, Spain*

## Sañudo Jaime

*Department of Physics, Faculty of Science, Universidad de Extremadura, Badajoz, Spain Also at BIFI, Institute for Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, Zaragoza, Spain*
