diff --git a/man3/ptsname.3 b/man3/ptsname.3
index 7dfccb438..87563ea93 100644
--- a/man3/ptsname.3
+++ b/man3/ptsname.3
@@ -92,7 +92,8 @@ T{
 T}	Thread safety	MT-Safe
 .TE
 .SH CONFORMING TO
-POSIX.1-2001, POSIX.1-2008.
+.BR ptsname ():
+ POSIX.1-2001, POSIX.1-2008.
 
 .BR ptsname ()
 is part of the UNIX 98 pseudoterminal support (see