docs: Documentation update
diff --git a/docs/doxygen.h b/docs/doxygen.h
index 52653bb..02d45c1 100644
--- a/docs/doxygen.h
+++ b/docs/doxygen.h
@@ -3,3 +3,21 @@
*
* Please refer to <a href="../index.html">ndnSIM documentation page</a>
*/
+
+// explicit instantiation and registering
+
+/**
+ * @brief ContentStore with LRU cache replacement policy
+ */
+template class ContentStoreImpl<lru_policy_traits>;
+/**
+ * @brief ContentStore with random cache replacement policy
+ */
+
+template class ContentStoreImpl<random_policy_traits>;
+
+/**
+ * @brief ContentStore with FIFO cache replacement policy
+ */
+template class ContentStoreImpl<fifo_policy_traits>;
+