**Author details**

Alfredo Bermúdez1,2, Dolores Gómez1,2 and Pablo Venegas<sup>3</sup> \*

1 Universidade de Santiago de Compostela, Santiago de Compostela, Spain

2 Galician Center for Mathematical Research and Technology (CITMAga), Galicia, Spain

3 GIMNAP, Universidad del Bío-Bío, Concepción, Chile

\*Address all correspondence to: pvenegas@ubiobio.cl

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