Disappearing of a “bolus” with increasing magnetic field: Peristaltic flows Tayyaba Ehsan, Hafiz Junaid Anjum and Saleem Asghar Eur. Phys. J. Plus, 134 12 (2019) 604 Published online: 05 December 2019 DOI: 10.1140/epjp/i2019-13089-9