équation iconale
1983 / The eikonal equation / Manfred Schroeder / The Mathematical Intelligencer 5 (1983) p. 36 [doi]
1999 / Geometric-optical Rays, Poynting's Vector, and Field Momenta / Masud Mansuripur / Optics and Photonics News 10 (1999) p. 53 [lien]