1SWM:
reference: X-ray crystal structure of the ferric sperm whale myoglobin: imidazole complex at 2.0 A resolution., Lionetti C, Guanziroli MG, Frigerio F, Ascenzi P, Bolognesi M, J Mol Biol 1991 Feb 5;217(3):409-12. PMID: 1994031

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