diff --git a/CMakeLists.txt b/CMakeLists.txt
index 091cd89..2c00955 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -383,7 +383,7 @@ if(CIFPP_DOWNLOAD_CCD)
 			endif()
 
 			add_custom_command(OUTPUT ${COMPONENTS_CIF}
-				COMMAND ${GUNZIP} ${COMPONENTS_CIF}.gz
+				COMMAND "${GUNZIP}" ${COMPONENTS_CIF}.gz
 				WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}/rsrc/)
 
 			add_custom_target(COMPONENTS ALL DEPENDS ${COMPONENTS_CIF})