TY  - JOUR
AU  - Ya. B. Zel'dovich
TI  - The number of quanta as an invariant of classical electromagnetic field
JO  - Doklady Akademii Nauk
PY  - 1965
SP  - 1359
EP  - 1360
VL  - 163
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1965_163_6_a16/
LA  - ru
ID  - DAN_1965_163_6_a16
ER  -