diff --git a/doc/top/top.n b/doc/top/top.n
index 7013f3616..7067bf828 100644
--- a/doc/top/top.n
+++ b/doc/top/top.n
@@ -1,6 +1,8 @@
 .ND
 .tr ~
 .ds >. .
+.ds [. [
+.ds .] ]
 .TL
 The ACK Target Optimizer
 .AU