(en) Keilin, D. (1925). On cytochrome, a respiratory pigment, common to animals, yeast, and higher plants. Proc. R. Soc. Lond. B98 (690): 312–339. DOI: 10.1098/rspb.1925.0039.
(en) Michel H, Behr J, Harrenga A, Kannt A. (1998). Cytochrome C Oxidase: Structure and Spectroscopy. Annual Review of Biophysics and Biomolecular Structure27: 329-356. DOI: 10.1146/annurev.biophys.27.1.329.