Electro-osmotic flow of couple stress fluids in a micro-channel propagated by peristalsis Dharmendra Tripathi, Ashu Yadav and O. Anwar Bég Eur. Phys. J. Plus, 132 4 (2017) 173 Published online: 14 April 2017 DOI: 10.1140/epjp/i2017-11416-x