diff --git a/Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_2.C b/Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_2.cpp
similarity index 100%
rename from Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_2.C
rename to Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_2.cpp
diff --git a/Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_3.C b/Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_3.cpp
similarity index 100%
rename from Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_3.C
rename to Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_3.cpp
diff --git a/Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_d.C b/Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_d.cpp
similarity index 100%
rename from Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_d.C
rename to Min_annulus_d/test/Min_annulus_d/test_Min_annulus_d_d.cpp