1. J.I. Ortega, J.I. Burgaleta, F.M. Téllez: submitted to Journal of Solar Energy Engineering (2008).
2. Y. Shuai, X.L. Xia, H.P. Tan: submitted to Solar Energy (2008).
3. J.C. Daly: submitted to Applied Optics (2009).
4. J.M. Lata, M.Á. Rodríguez, M.A. Lara: submitted to Journal of Solar Energy Engineering (2008).
5. H. Hasuike, H. Yoshizawa, H. Suzuki: submitted to Solar Energy (2006).