Back to matchesWe found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleAspartic Proteinase Phylogeny and the Origin of Pregnancy-Associated Glycoproteins.AuthorsHughes, Austin L.; Green, Jonathan A.; Piontkivska, Helen; Roberts, R. MichaelPublicationMolecular Biology & Evolution, 2003, Vol 20, Issue 11, p1940ISSN0737-4038Publication typeArticleDOI10.1093/molbev/msg217