Open Access
Research Article
Volume 27, 2020
Article Number 10
Number of page(s) 13
Published online 12 February 2020

© L. Djamouko-Djonkam et al., published by EDP Sciences, 2020

Licence Creative Commons
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.