@article{10_1017_S0017089500009290,
     author = {Hare, Kathryn E.},
     title = {Union results for thin sets},
     journal = {Glasgow mathematical journal},
     pages = {241--254},
     year = {1990},
     volume = {32},
     number = {2},
     doi = {10.1017/S0017089500009290},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500009290/}
}