Thomas Weiss, M. Schaeferling, Harald Gießen, N. A. Gippius, S. G. Tikhodeev, W. Langbein, and E. A. Muljarov. Analytical normalization of resonant states in photonic crystal slabs and periodic arrays of nanoantennas at oblique incidence. PHYSICAL REVIEW B, (96)4AMER PHYSICAL SOC, July 2017. [PUMA: array crystal nanoantenna photonic]