Asymptotic densities from the modified Montroll-Weiss equation for coupled CTRWs Erez Aghion, David A. Kessler and Eli Barkai Eur. Phys. J. B, 91 1 (2018) 17 Published online: 25 January 2018 DOI: 10.1140/epjb/e2017-80401-4