1R3M:
reference: Crystal structure of the dimeric unswapped form of bovine seminal ribonuclease., Berisio R, Sica F, De Lorenzo C, Di Fiore A, Piccoli R, Zagari A, Mazzarella L, FEBS Lett 2003 Nov 6;554(1-2):105-10. PMID: 14596923

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