@article{PORMA_1971__30_1_115136,
     author = {Johnson, William B. and Shive, Robert A. jr.},
     title = {Linear contraction mappings},
     journal = {Portugaliae mathematica},
     pages = {41--44},
     publisher = {mathdoc},
     volume = {30},
     number = {1},
     year = {1971},
     mrnumber = {0305022},
     zbl = {0228.47004},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1971__30_1_115136/}
}