@article{10_4153_CJM_1980_084_4,
     author = {Bisztriczky, Tibor and Rival, Ivan},
     title = {Continuous, {Slope-Preserving} {Maps} of {Simple} {Closed} {Curves}},
     journal = {Canadian journal of mathematics},
     pages = {1102--1113},
     year = {1980},
     volume = {32},
     number = {5},
     doi = {10.4153/CJM-1980-084-4},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1980-084-4/}
}