Richter, M., Baier, J., Prem, T., Oellerich, S., Francia, F., Venturoli, G., Oesterhelt, D., Southall, J., Cogdell, R., & Köhler, J. (2007). Symmetry matters for the electronic structure of core complexes from Rhodopseudomonas palustris and Rhodobacter sphaeroides PufX. Proceedings of the National Academy of Sciences, 104(16), 6661-6665. doi:10.1073/pnas.0611115104.