@article{TM_1975_135_a17,
     author = {G. Lassner and A. Uhlmann},
     title = {On {Op*-algebras} of unbounded operators},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {168--173},
     year = {1975},
     volume = {135},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TM_1975_135_a17/}
}