The simplest wormhole in Rastall and k-essence theories Kirill A. Bronnikov, Vinícius A. G. Barcellos, Laura P. de Carvalho and Júlio C. Fabris Eur. Phys. J. C, 81 5 (2021) 395 Published online: 06 May 2021 DOI: 10.1140/epjc/s10052-021-09164-y