TY - JOUR AU - L. D. Loveland AU - J. E. Valentine TI - Generalized midset properties characterize geodesic circles and intervals JO - Colloquium Mathematicum PY - 1977 SP - 231 EP - 241 VL - 38 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.4064/cm-38-2-231-241/ DO - 10.4064/cm-38-2-231-241 LA - en ID - 10_4064_cm_38_2_231_241 ER -