A Possible Common Origin of Poliovirus Proteins With Different Functions, by Gorbalenya, Donchenko, and Blinov, 1987
Cysteine Proteases of Positive Strand RNA Viruses and Chymotrypsin-Like Serine Proteases: A Distinct Protein Superfamily With A Common Structural Fold, by Gorbalenya, Donchenko, Blinov and Koonin, 1988
Enzyme Evolution: The Two Serine Tale May Have Different Ends, 1983-1993
Sobemovirus genome appears to encode a serine protease related to cysteine proteases of picornaviruses, by Gorbalenya, Koonin, Vladimir, et. al., 1988