TY - JOUR AU - Grant Cairns AU - Stacey Mendan TI - An improvement of a result of Zverovich - Zverovich JO - Ars Mathematica Contemporanea PY - 2016 SP - 79 EP - 83 VL - 10 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.26493/1855-3974.451.1a2/ DO - 10.26493/1855-3974.451.1a2 LA - en ID - 10_26493_1855_3974_451_1a2 ER -