Henderson, R; Baldwin, JM; Ceska, TA; Zemlin, F; Beckmann, E; Downing, KH (1990). "Model for the structure of bacteriorhodopsin based on high-resolution electron cryo-microscopy". Journal of Molecular Biology. 213: 899–929. doi:10.1016/S0022-2836(05)80271-2. PMID2359127.
Henderson, R; Baldwin, JM; Ceska, TA; Zemlin, F; Beckmann, E; Downing, KH (1990). "Model for the structure of bacteriorhodopsin based on high-resolution electron cryo-microscopy". Journal of Molecular Biology. 213: 899–929. doi:10.1016/S0022-2836(05)80271-2. PMID2359127.