Entropy analysis for the peristaltic flow of third grade fluid with variable thermal conductivity Tasawar Hayat, Sadaf Nawaz, Ahmed Alsaedi and Bashir Ahmad Eur. Phys. J. Plus, 135 5 (2020) 421 Published online: 19 May 2020 DOI: 10.1140/epjp/s13360-020-00421-9