docs: Update documentation and Doxygen documentation generation
diff --git a/apps/ndn-consumer-zipf-mandelbrot.h b/apps/ndn-consumer-zipf-mandelbrot.h
index b9f4d17..d9333b3 100644
--- a/apps/ndn-consumer-zipf-mandelbrot.h
+++ b/apps/ndn-consumer-zipf-mandelbrot.h
@@ -38,7 +38,7 @@
namespace ndn {
/**
- * @ingroup ndn
+ * @ingroup ndn-apps
* @brief NDN app requesting contents following Zipf-Mandelbrot Distbituion
*
* The class implements an app which requests contents following Zipf-Mandelbrot Distribution