Never Give Up: Learning Directed Exploration Strategies. - Badia, Adrià Puigdomènech; Sprechmann, Pablo; Vitvitskyi, Alex; Guo, Zhaohan Daniel; Piot, Bilal; Kapturowski, Steven; Tieleman, Olivier; Arjovsky, Martín; Pritzel, Alexander; Bolt, Andrew; Blundell, Charles (2020)