Theoretical investigation of the doubly stratified flow of an Eyring-Powell nanomaterial via heat generation/absorptionM. Ijaz Khan, M. Waqas, A. Alsaedi, T. Hayat and M. Imran KhanEur. Phys. J. Plus, 132 11 (2017) 489DOI: https://doi.org/10.1140/epjp/i2017-11753-8