Matthies, D., Preiss, L., Klyszejko, A. L., Muller, D. J., Cook, G. M., Vonck, J., & Meier, T. (2009). The c13 Ring from a Thermoalkaliphilic ATP Synthase Reveals an Extended Diameter Due to a Special Structural Region. Journal of Molecular Biology, 388(3), 611-618.