@article{PMIHES_1964__19__69_0,
     author = {John F. P. Hudson and Eric Christopher Zeeman},
     title = {On combinatorial isotopy},
     journal = {Publications Math\'ematiques de l'IH\'ES},
     pages = {69--94},
     year = {1964},
     publisher = {Institut des Hautes \'Etudes Scientifiques},
     volume = {19},
     doi = {10.1007/BF02684797},
     zbl = {0136.21201},
     mrnumber = {163318},
     language = {en},
     url = {https://pmihes.centre-mersenne.org/articles/10.1007/BF02684797/}
}