diff --git a/Common/CMakeLists.txt b/Common/CMakeLists.txt
index 9d79a3df8f5806ace6b21b03bd6bfa52762e4ac7..5a51c07d790ee782650521ba7f154f3e8fccdc71 100644
--- a/Common/CMakeLists.txt
+++ b/Common/CMakeLists.txt
@@ -4,34 +4,34 @@ target_sources(test_set_all_outerm PRIVATE derived_types.f90
   spher_polyline_area.f90 shpc_create.f90 write_eddy.f90 shpc_close.f90)
 target_sources(test_max_speed_contour_ssh PRIVATE derived_types.f90)
 target_sources(test_nearby_extr PRIVATE derived_types.f90 read_snapshot.f90
-  read_eddy.f90 read_field_indices.F90 shpc_open.F90 shpc_close.f90)
+  read_eddy.f90 read_field_indices.f90 shpc_open.f90 shpc_close.f90)
 target_sources(test_set_max_speed PRIVATE derived_types.f90
-  spher_polyline_area.f90 shpc_open.F90 shpc_close.f90 read_field_indices.F90
+  spher_polyline_area.f90 shpc_open.f90 shpc_close.f90 read_field_indices.f90
   read_eddy.f90 shpc_create.f90 write_eddy.f90)
 target_sources(test_spher_polyline_area PRIVATE spher_polyline_area.f90)
 target_sources(inst_eddies PRIVATE write_eddy.f90 spher_polyline_area.f90
-  derived_types.f90 shpc_create.f90 shpc_close.f90 shpc_open.F90
-  read_field_indices.F90)
+  derived_types.f90 shpc_create.f90 shpc_close.f90 shpc_open.f90
+  read_field_indices.f90)
 
 if(MPI_Fortran_HAVE_F08_MODULE)
   target_sources(test_overlap PRIVATE derived_types.f90 read_snapshot.f90
-    spher_polyline_area.f90 read_eddy.f90 read_field_indices.F90 write_eddy.f90
-    shpc_open.F90 shpc_close.f90)
+    spher_polyline_area.f90 read_eddy.f90 read_field_indices.f90 write_eddy.f90
+    shpc_open.f90 shpc_close.f90)
   target_sources(test_read_snapshot PRIVATE derived_types.f90 shpc_create.f90
-    read_snapshot.f90 write_eddy.f90 read_eddy.f90 read_field_indices.F90
-    shpc_open.F90 shpc_close.f90)
+    read_snapshot.f90 write_eddy.f90 read_eddy.f90 read_field_indices.f90
+    shpc_open.f90 shpc_close.f90)
   target_sources(test_spher_polygon_area PRIVATE spher_polyline_area.f90)
   target_sources(test_weight PRIVATE derived_types.f90)
   target_sources(test_read_eddy PRIVATE derived_types.f90 shpc_create.f90
-    read_eddy.f90 write_eddy.f90 read_field_indices.F90 shpc_open.F90
+    read_eddy.f90 write_eddy.f90 read_field_indices.f90 shpc_open.f90
     shpc_close.f90)
-  target_sources(test_send_recv PRIVATE read_field_indices.F90
+  target_sources(test_send_recv PRIVATE read_field_indices.f90
     read_snapshot.f90 write_eddy.f90 shpc_create.f90 read_eddy.f90
-    derived_types.f90 shpc_open.F90 shpc_close.f90)
-  target_sources(test_get_dispatch_snap PRIVATE read_field_indices.F90
+    derived_types.f90 shpc_open.f90 shpc_close.f90)
+  target_sources(test_get_dispatch_snap PRIVATE read_field_indices.f90
     read_snapshot.f90 shpc_create.f90 write_eddy.f90 read_eddy.f90
-    derived_types.f90 shpc_open.F90 shpc_close.f90)
-  target_sources(eddy_graph PRIVATE shpc_open.F90 shpc_close.f90
-    read_field_indices.F90 read_snapshot.f90 spher_polyline_area.f90
+    derived_types.f90 shpc_open.f90 shpc_close.f90)
+  target_sources(eddy_graph PRIVATE shpc_open.f90 shpc_close.f90
+    read_field_indices.f90 read_snapshot.f90 spher_polyline_area.f90
     read_eddy.f90 write_eddy.f90 derived_types.f90)
 endif()
diff --git a/Common/read_field_indices.F90 b/Common/read_field_indices.f90
similarity index 100%
rename from Common/read_field_indices.F90
rename to Common/read_field_indices.f90
diff --git a/Common/shpc_open.F90 b/Common/shpc_open.f90
similarity index 100%
rename from Common/shpc_open.F90
rename to Common/shpc_open.f90