@article{MASLO_2007_57_6_a6,
     author = {Pulmannov\'a, Sylvia and Vincekov\'a, E.},
     title = {Remarks on the order for quantum observables},
     journal = {Mathematica slovaca},
     pages = {589--600},
     year = {2007},
     volume = {57},
     number = {6},
     mrnumber = {2358400},
     zbl = {1164.81001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/MASLO_2007_57_6_a6/}
}