to list some of the articles:
1. Li, Yanjiao, et al. "A review on development of nanofluid preparation and characterization." Powder Technology 196.2 (2009): 89-101.
2. Sidik, Nor Azwadi Che, et al. "A review on preparation methods and challenges of nanofluids." International Communications in Heat and Mass Transfer 54 (2014): 115-125.