Bi-paratopic and multivalent VH domains block ACE2 binding and neutralize SARS-CoV-2Bracken C, Lim S, Solomon P, Rettko N, Nguyen D, Zha B, Schaefer K, Byrnes J, Zhou J, Lui I, Liu J, Pance K, QCRG Structural Biology Consortium, Zhou X, Leung K, Wells J. Nature Chemical Biology