M. B. Schilling, L. M. Schoop, B. V. Lotsch, M. Dressel, and A. V. Pronin. Flat Optical Conductivity in ZrSiS due to Two-Dimensional Dirac Bands. Phys. Rev. Lett., (119)18:187401, American Physical Society, November 2017. [PUMA: Dirac ZrSiS bands conductivity] URL