@article{10_4153_CMB_1978_002_8,
     author = {Clarke, Frank H.},
     title = {Pointwise {Contraction} {Criteria} for the {Existence} of {Fixed} {Points}},
     journal = {Canadian mathematical bulletin},
     pages = {7--11},
     year = {1978},
     volume = {21},
     number = {1},
     doi = {10.4153/CMB-1978-002-8},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1978-002-8/}
}