diff --git a/include/canbus/canopen.h b/include/canbus/canopen.h
index 2171fc2f378..a3a43c0a66a 100644
--- a/include/canbus/canopen.h
+++ b/include/canbus/canopen.h
@@ -4,6 +4,13 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+
+/**
+ * @defgroup CAN CAN BUS
+ * @{
+ * @}
+ */
+
 /**
  * @brief CANopen Network Stack
  * @defgroup canopen CANopen Network Stack
diff --git a/include/random/rand32.h b/include/random/rand32.h
index a0651490529..b8ed332edf2 100644
--- a/include/random/rand32.h
+++ b/include/random/rand32.h
@@ -26,6 +26,7 @@
 /**
  * @brief Random Function APIs
  * @defgroup random_api Random Function APIs
+ * @ingroup crypto
  * @{
  */
 
diff --git a/include/settings/settings.h b/include/settings/settings.h
index 4ee101f9f46..d7d8b52d5c5 100644
--- a/include/settings/settings.h
+++ b/include/settings/settings.h
@@ -17,8 +17,15 @@
 extern "C" {
 #endif
 
+
 /**
- * @defgroup settings Settings subsystem
+ * @defgroup file_system_storage File System Storage
+ * @{
+ * @}
+ */
+
+/**
+ * @defgroup settings Settings
  * @ingroup file_system_storage
  * @{
  */
@@ -351,7 +358,7 @@ int settings_commit_subtree(const char *subtree);
 
 /**
  * @defgroup settings_backend Settings backend interface
- * @ingroup file_system_storage
+ * @ingroup settings
  * @{
  */