diff --git a/doc/sphinx/load_config.py b/doc/sphinx/load_config.py
index 301a21a..eeb394b 100644
--- a/doc/sphinx/load_config.py
+++ b/doc/sphinx/load_config.py
@@ -21,6 +21,29 @@
         and os.path.normpath(namespace["__file__"]) != os.path.normpath(config_file) ):
         config_file = os.path.abspath(config_file)
 
+        # Let's avoid one conf.py file just due to latex_documents
+        start = config_file.find('Documentation/')
+        if start >= 0:
+            start = config_file.find('/', start + 1)
+
+        end = config_file.rfind('/')
+        if start >= 0 and end > 0:
+            dir = config_file[start + 1:end]
+
+            print("source directory: %s" % dir)
+            new_latex_docs = []
+            latex_documents = namespace['latex_documents']
+
+            for l in latex_documents:
+                if l[0].find(dir + '/') == 0:
+                    has = True
+                    fn = l[0][len(dir) + 1:]
+                    new_latex_docs.append((fn, l[1], l[2], l[3], l[4]))
+                    break
+
+            namespace['latex_documents'] = new_latex_docs
+
+        # If there is an extra conf.py file, load it
         if os.path.isfile(config_file):
             sys.stdout.write("load additional sphinx-config: %s\n" % config_file)
             config = namespace.copy()
@@ -29,4 +52,6 @@
             del config['__file__']
             namespace.update(config)
         else:
-            sys.stderr.write("WARNING: additional sphinx-config not found: %s\n" % config_file)
+            config = namespace.copy()
+            config['tags'].add("subproject")
+            namespace.update(config)