@article{TMF_1991_87_1_a2,
     author = {A. Yu. Artem'ev},
     title = {Quantum beats of light polarization and condition of complete positivity},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {34--39},
     year = {1991},
     volume = {87},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1991_87_1_a2/}
}