diff --git a/internal/ceres/polynomial_test.cc b/internal/ceres/polynomial_test.cc
index 7ac129e..f2fd19e 100644
--- a/internal/ceres/polynomial_test.cc
+++ b/internal/ceres/polynomial_test.cc
@@ -167,7 +167,7 @@
 
 TEST(Polynomial, QuadraticPolynomialWithCloseRootsWorks) {
   const double roots[2] = { 42.42, 42.43 };
-  RunPolynomialTestRealRoots(roots, true, false, 2 * psilonLoose);
+  RunPolynomialTestRealRoots(roots, true, false, 2 * kEpsilonLoose);
 }
 
 TEST(Polynomial, QuadraticPolynomialWithComplexRootsWorks) {