ZINC20 - A Free Ultralarge-Scale Chemical Database for Ligand Discovery. - John J. Irwin; Khanh G. Tang; Jennifer Young; Chinzorig Dandarchuluun; Benjamin R. Wong; Munkhzul Khurelbaatar; Yurii S. Moroz; John W. Mayfield; Roger A. Sayle (J. Chem. Inf. Model., 2020)