@article{10_21136_CMJ_1955_100166,
     author = {Alda, V\'aclav},
     title = {On conditional expectations},
     journal = {Czechoslovak Mathematical Journal},
     pages = {503--505},
     publisher = {mathdoc},
     volume = {05},
     number = {4},
     year = {1955},
     doi = {10.21136/CMJ.1955.100166},
     mrnumber = {0080394},
     zbl = {0068.32606},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1955.100166/}
}