@article{MS2_1963__13_165857,
     author = {Lars C. Mejlbo},
     title = {On the {Solution} of the {Commutation} {Relation} {PQ} - {QP} = {-iI.}},
     journal = {Mathematica Scandinavica},
     pages = {129--139},
     publisher = {mathdoc},
     volume = {13},
     year = {1963},
     zbl = {0135.36404},
     url = {http://geodesic.mathdoc.fr/item/MS2_1963__13_165857/}
}