Index: head/contrib/nvi/man/vi.1
===================================================================
--- head/contrib/nvi/man/vi.1
+++ head/contrib/nvi/man/vi.1
@@ -12,7 +12,7 @@
 .\" that you would have purchased it, or if any company wishes to
 .\" redistribute it, contributions to the authors would be appreciated.
 .\"
-.Dd November 2, 2013
+.Dd September 25, 2020
 .Dt VI 1
 .Os
 .Sh NAME
@@ -2743,6 +2743,10 @@
 .Xr ctags 1 ,
 .Xr iconv 1 ,
 .Xr re_format 7
+.Rs
+.%T vi/ex reference manual
+.%U https://docs.freebsd.org/44doc/usd/13.viref/paper.pdf
+.Re
 .Sh STANDARDS
 .Nm nex Ns / Ns Nm nvi
 is close to