journalArticle Renewable Energy Focus 35 DOI 10.1016/j.ref.2020.10.007 Hallal J. Hammoud M. Moussa T. Experimental optimization of the Si photovoltaic panels cooling system on maximum allowable temperature criteria 178-181 2020 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85097206891&doi=10.1016%2fj.ref.2020.10.007&partnerID=40&md5=1ba2577328d557efd2986cc4f54b0520 Scopus