On the applications of nanofluids to enhance the performance of solar collectors: A comparative analysis of Atangana-Baleanu and Caputo-Fabrizio fractional modelsNadeem Ahmad Sheikh, Farhad Ali, Ilyas Khan, Madeha Gohar and Muhammad SaqibEur. Phys. J. Plus, 132 12 (2017) 540DOI: https://doi.org/10.1140/epjp/i2017-11809-9