Eisenman , George, Jarl Hägglund, John Sandblom, and Bruce Enos. 1980. “The Current-Voltage Behavior of Ion Channels: Important Features of the Energy Profile of the Gramicidin Channel Deduced from the Conductance-Voltage Characteristic in the Limit of Low Ion Concentration”. Upsala Journal of Medical Sciences 85 (3):247-57. https://doi.org/10.3109/03009738009179195.