• E. Pastorczak, N. I. Gidopoulos, K. Pernal, Calculation of electronic excited states of molecules using the Helmholtz free-energy minimum principle, Phys. Rev. A 87(6), 062501, 2013
  • E. Pastorczak, N. I. Gidopoulos, K. Pernal, Calculation of electronic excited states of molecules using the Helmholtz free-energy minimum principle, Phys. Rev. A 87(6), 062501, 2013