Irons, T. J., Furness, J. W., Ryley, M. S., Zemen, J., Helgaker, T., & Teale, A. M. (2017). Connections between variation principles at the interface of wave-function and density-functional theories. Journal of Chemical Physics, 147(13), Article 134107. https://doi.org/10.1063/1.4985883