@article{10_4064_cm_38_2_231_241,
     author = {L. D. Loveland and J. E. Valentine},
     title = {Generalized midset properties characterize geodesic circles and intervals},
     journal = {Colloquium Mathematicum},
     pages = {231--241},
     publisher = {mathdoc},
     volume = {38},
     number = {2},
     year = {1977},
     doi = {10.4064/cm-38-2-231-241},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-38-2-231-241/}
}