diff --git a/HISTORY.md b/HISTORY.md
index e1a3cc6100..aed0015396 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -27,6 +27,8 @@
   * Add support for probabilistic KDE (kernel density estimation) error bounds
     when using the Gaussian kernel (#1934).
 
+  * Fix negative distances for cover tree computation (#1979).
+
 ### mlpack 3.1.1
 ###### 2019-05-26
   * Fix random forest bug for numerical-only data (#1887).