@article{10_4064_sm204_3_4,
     author = {Takateru Okayasu and Jan Stochel and Yasunori Ueda},
     title = {On a binary relation between normal operators},
     journal = {Studia Mathematica},
     pages = {247--264},
     publisher = {mathdoc},
     volume = {204},
     number = {3},
     year = {2011},
     doi = {10.4064/sm204-3-4},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm204-3-4/}
}