Use .Mt to mark up email addresses.

docs/man/nginx.8

diff --git a/docs/man/nginx.8 b/docs/man/nginx.8
index f2ed9f7..10db3e6 100644
--- a/docs/man/nginx.8
+++ b/docs/man/nginx.8
@@ -205,10 +205,10 @@
 started in 2002, with the first public release on October 4, 2004.
 .Sh AUTHORS
 .An -nosplit
-.An Igor Sysoev Aq igor@sysoev.ru .
+.An Igor Sysoev Aq Mt igor@sysoev.ru .
 .Pp
 This manual page was originally written by
-.An Sergey A. Osokin Aq osa@FreeBSD.org.ru
+.An Sergey A. Osokin Aq Mt osa@FreeBSD.org.ru
 as a result of compiling many
 .Nm
 documents from all over the world.