1 files changed, 1 insertions, 1 deletions
diff --git a/enum.c b/enum.c
index 88d6730ce8..8a791cc63d 100644
--- a/enum.c
+++ b/enum.c
@@ -3903,7 +3903,7 @@ sum_iter_Kahan_Babuska(VALUE i, struct enum_sum_memo *memo)
 {
     /*
      * Kahan-Babuska balancing compensated summation algorithm
-     * See http://link.springer.com/article/10.1007/s00607-005-0139-x
+     * See https://link.springer.com/article/10.1007/s00607-005-0139-x
      */
     double x;