diff --git a/Doxyfile b/Doxyfile
index 07a715a3c..8ea7467fe 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -641,6 +641,7 @@ WARN_LOGFILE           =
 INPUT                  = gtsam/base \
                          gtsam/geometry \
                          gtsam/inference \
+                         gtsam/discrete \
                          gtsam/linear \
                          gtsam/nonlinear \
                          gtsam/slam \