1. Department of Applied Physics CINVESTAV-IPN Antigua Carretera a Progreso km 6 Mérida, Yucatán 97310 México
2. Department of Physical Chemical and Natural Systems Universidad Pablo de Olavide Carretera de Utrera km 1 Sevilla 41013 Spain
3. Thin-Film Photovoltaics – partner in EnergyVille and Solliance, imec Thor Park 8320 3600 Genk Belgium
4. Mathematical Sciences University of Southampton Southampton SO17 1BJ UK