diff --git a/owlps-positioning/src/minmax.cc b/owlps-positioning/src/minmax.cc
index d3c3e47..030ed8f 100644
--- a/owlps-positioning/src/minmax.cc
+++ b/owlps-positioning/src/minmax.cc
@@ -25,7 +25,7 @@ Point3D MinMax::multilaterate(
               if (dist > d_max)
                 d_max = dist ;
             }
-          if (d_max < min)
+          if (d_max <= min)
             {
               min = d_max ;
               centre.set_coordinates(x, y, z) ;
diff --git a/owlps-positioning/src/minmax.hh b/owlps-positioning/src/minmax.hh
index 0fe4633..b15dce8 100644
--- a/owlps-positioning/src/minmax.hh
+++ b/owlps-positioning/src/minmax.hh
@@ -7,8 +7,8 @@
 class MinMax: public MultilaterationMethod
 {
 protected:
-  const Point3D &start ;
-  const Point3D &stop ;
+  const Point3D start ;
+  const Point3D stop ;
   float step ;
 
   static const float MINMAX_DEFAULT_STEP = 0.5 ;