diff --git a/libsrc/CMakeLists.txt b/libsrc/CMakeLists.txt
index 65a3f87..30a008d 100644
--- a/libsrc/CMakeLists.txt
+++ b/libsrc/CMakeLists.txt
@@ -61,7 +61,7 @@ IF(HAVE_M4)
 IF(NOT MSVC)
   ADD_CUSTOM_TARGET(manpage ALL
 
-    COMMAND ${NC_M4} ${ARGS_MANPAGE} '${CMAKE_CURRENT_BINARY_DIR}/netcdf.m4' > '${CMAKE_CURRENT_BINARY_DIR}/netcdf.3'
+    COMMAND ${NC_M4} ${ARGS_MANPAGE} "${CMAKE_CURRENT_BINARY_DIR}/netcdf.m4" > "${CMAKE_CURRENT_BINARY_DIR}/netcdf.3" VERBATIM
     WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
     )