diff --git a/appveyor.yml b/appveyor.yml
index 7a98360c..f3e850a7 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -22,7 +22,7 @@ install:
   - cd CGAL-4.11.1
   - mkdir build
   - cd build
-  - cmake ../ -DGMP_INCLUDE_DIR=%APPVEYOR_BUILD_FOLDER%\CGAL-4.11.1\auxiliary\gmp\include -DGMP_LIBRARIES=%APPVEYOR_BUILD_FOLDER%\CGAL-4.11.1\auxiliary\gmp\lib
+  - cmake ../ -DGMP_INCLUDE_DIR=%APPVEYOR_BUILD_FOLDER%\CGAL-4.11.1\auxiliary\gmp\include -DGMP_LIBRARIES=%APPVEYOR_BUILD_FOLDER%\CGAL-4.11.1\auxiliary\gmp\lib  -DMPFR_INCLUDE_DIR=%APPVEYOR_BUILD_FOLDER%\CGAL-4.11.1\auxiliary\gmp\include -DMPFR_LIBRARIES=%APPVEYOR_BUILD_FOLDER%\CGAL-4.11.1\auxiliary\gmp\lib
   - msbuild /p:Configuration=Release ALL_BUILD.vcxproj
     
 build: false