diff --git a/.gitmodules b/.gitmodules
index 07e85b6736a693f6e94b891f0c59f9153c0daa1f..f2c4e570523a1dcbce8c8c05c1720f793d871f21 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,9 +1,9 @@
 [submodule "doc_module_gtf"]
 	path = doc_module_gtf
-	url = http://gitlab.veremes.net/Documentation/doc_module_gtf.git
+	url = https://gitlab.veremes.net/Documentation/doc_module_gtf.git
 [submodule "doc_module_vitis"]
 	path = doc_module_vitis
-	url = http://gitlab.veremes.net/Documentation/doc_module_vitis.git
+	url = https://gitlab.veremes.net/Documentation/doc_module_vitis.git
 [submodule "doc_module_studio"]
 	path = doc_module_studio
-	url = http://gitlab.veremes.net/Documentation/doc_module_studio.git
+	url = https://gitlab.veremes.net/Documentation/doc_module_studio.git