@article{oai:tsukuba.repo.nii.ac.jp:00017170,
 author = {George, Michael A. A.},
 issue = {1},
 journal = {Tsukuba journal of mathematics},
 month = {Jun},
 pages = {13--45},
 title = {On the smoothing problem},
 volume = {25},
 year = {2001}
}