diff --git a/development/cmake/doc/CMakeLists.txt b/development/cmake/doc/CMakeLists.txt
index 5bd50a0a30..9379ae6c87 100644
--- a/development/cmake/doc/CMakeLists.txt
+++ b/development/cmake/doc/CMakeLists.txt
@@ -32,15 +32,15 @@ foreach(_rel_doc ${_rel_lyx_docs})
     add_custom_command(
       OUTPUT "${_created_doc}"
       COMMAND ${CMAKE_COMMAND}
-	-DLYX_PYTHON_EXECUTABLE=${LYX_PYTHON_EXECUTABLE}
-	-DTOP_CMAKE_PATH=${TOP_CMAKE_PATH}
+        -DLYX_PYTHON_EXECUTABLE=${LYX_PYTHON_EXECUTABLE}
+        -DTOP_CMAKE_PATH=${TOP_CMAKE_PATH}
         -DLYX_USERDIR_VER=${LYX_USERDIR_VER}
-	-DLYX_DIR_VER=${LYX_DIR_VER}
-	-DTOP_SRC_DIR=${TOP_SRC_DIR}
-	-DREL_DIR=${_rel_dir_part}
-	-DSOURCE=${_rel_doc}
-	-DCREATED=${_created_doc}
-	-P "${TOP_CMAKE_PATH}/doc/ReplaceValues.cmake"
+        -DLYX_DIR_VER=${LYX_DIR_VER}
+        -DTOP_SRC_DIR=${TOP_SRC_DIR}
+        -DREL_DIR=${_rel_dir_part}
+        -DSOURCE=${_rel_doc}
+        -DCREATED=${_created_doc}
+        -P "${TOP_CMAKE_PATH}/doc/ReplaceValues.cmake"
       DEPENDS "${TOP_SRC_DIR}/lib/doc/${_rel_doc}" "${TOP_CMAKE_PATH}/doc/ReplaceValues.py"
       )
     install(FILES "${CMAKE_CURRENT_BINARY_DIR}/${_rel_doc}" DESTINATION "${LYX_DATA_SUBDIR}doc/${_rel_dir_part}")