diff --git a/probability/martingales.qmd b/probability/martingales.qmd
index a9e911e2..65801d06 100644
--- a/probability/martingales.qmd
+++ b/probability/martingales.qmd
@@ -596,4 +596,4 @@ The material in the introduction is taken from @Pollard2002, @Chang2007, and @De
 
 [post]: https://mathoverflow.net/a/357922/520224
 
-@exr-martingale-Robbins-Monroe is from @Bertsekas2000.
+@exr-martingale-Robbins-Monroe is from @Bertsekas2000. @exr-vec-almost-supermartingale is from @Mahajan:cdc2024a, which provides other vector generalizations of @thm-almost-supermartingale as well.