The SAMPL6 SAMPLing challenge: assessing the reliability and efficiency of binding free energy calculations. - Rizzi, Andrea; Jensen, Travis; Slochower, David R.; Aldeghi, Matteo; Gapsys, Vytautas; Ntekoumes, Dimitris; Bosisio, Stefano; Papadourakis, Michail; Henriksen, Niel M.; de Groot, Bert L.; Cournia, Zoe; Dickson, Alex; et al. (Journal of Computer-Aided Molecular Design, 2020)