@article{10_1017_S0017089500032559,
     author = {Yang, Youngoh},
     title = {On a class of operators},
     journal = {Glasgow mathematical journal},
     pages = {237--240},
     year = {1998},
     volume = {40},
     number = {2},
     doi = {10.1017/S0017089500032559},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500032559/}
}