diff --git a/arch/platform/zoul/contiki-conf.h b/arch/platform/zoul/contiki-conf.h
index 42f6661e1..35d4ebc6d 100644
--- a/arch/platform/zoul/contiki-conf.h
+++ b/arch/platform/zoul/contiki-conf.h
@@ -29,7 +29,7 @@
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 /**
- * \addtogroup platform
+ * \addtogroup zoul-core
  * @{
  *
  * \defgroup zoul-platforms Zolertia Zoul platforms
diff --git a/arch/platform/zoul/doxygen-group.txt b/arch/platform/zoul/doxygen-group.txt
new file mode 100644
index 000000000..9090c2390
--- /dev/null
+++ b/arch/platform/zoul/doxygen-group.txt
@@ -0,0 +1,4 @@
+/**
+ * \defgroup zoul-core Zolertia Zoul-based platforms
+ * \ingroup cc2538-platforms
+ */
diff --git a/arch/platform/zoul/platform.c b/arch/platform/zoul/platform.c
index d428decbb..f570b377a 100644
--- a/arch/platform/zoul/platform.c
+++ b/arch/platform/zoul/platform.c
@@ -30,7 +30,7 @@
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 /**
- * \addtogroup platform
+ * \addtogroup zoul-core
  * @{
  *
  * \defgroup zoul Zolertia Zoul core module