@article{TMF_1991_89_3_a5,
     author = {V. N. Popov and V. S. Yarunin},
     title = {Photon phase operator},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {395--401},
     publisher = {mathdoc},
     volume = {89},
     number = {3},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1991_89_3_a5/}
}