diff --git a/tests/simulated2D.h b/tests/simulated2D.h
index b4f78ee3b..7f89d5ac2 100644
--- a/tests/simulated2D.h
+++ b/tests/simulated2D.h
@@ -144,7 +144,7 @@ namespace simulated2D {
 
     /// Return error and optional derivative
     Vector evaluateError(const Pose& x, OptionalMatrixType H) const override {
-      return (prior(x, H) - measured_);
+      return (simulated2D::prior(x, H) - measured_);
     }
 
     ~GenericPrior() override {}
diff --git a/tests/simulated3D.h b/tests/simulated3D.h
index 5cec78e4e..54481fcbb 100644
--- a/tests/simulated3D.h
+++ b/tests/simulated3D.h
@@ -92,7 +92,7 @@ struct PointPrior3D: public NoiseModelFactor1<Point3> {
    * @return Vector error between prior value and x (Dimension: 3)
    */
   Vector evaluateError(const Point3& x, OptionalMatrixType H) const override {
-    return prior(x, H) - measured_;
+    return simulated3D::prior(x, H) - measured_;
   }
 };