@article{ZNSL_1977_73_a15,
     author = {V. G. Kulakova},
     title = {Invariant means and conditional expectation operators},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {207--210},
     publisher = {mathdoc},
     volume = {73},
     year = {1977},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1977_73_a15/}
}