diff --git a/apps/app_festival.c b/apps/app_festival.c
index 1fa935e0b11370f3f5959ae8e4ee84762f08f2cc..678b8cd8601309e787bf32f5e295dd2dbd460a76 100644
--- a/apps/app_festival.c
+++ b/apps/app_festival.c
@@ -21,6 +21,8 @@
  * \brief Connect to festival
  *
  * \author Christos Ricudis <ricudis@itc.auth.gr>
+ *
+ * \extref  The Festival Speech Synthesis System - http://www.cstr.ed.ac.uk/projects/festival/
  * 
  * \ingroup applications
  */
diff --git a/apps/app_osplookup.c b/apps/app_osplookup.c
index 3adde50f2f6dbc5c43d946ce10bf472e0bad84d5..6ac668260987d5e39b4651415320705159676465 100644
--- a/apps/app_osplookup.c
+++ b/apps/app_osplookup.c
@@ -22,6 +22,9 @@
  *
  * \author Mark Spencer <markster@digium.com>
  *
+ * \extref The OSP Toolkit: http://www.transnexus.com
+ * \extref OpenSSL http://www.openssl.org
+ *
  * \ingroup applications
  */
 
diff --git a/apps/app_voicemail.c b/apps/app_voicemail.c
index f06c9dacc5622dceb69d1fad0e49f597e9b9db8e..5cb03c86aeaf502ed620afaa065d8ce31901064c 100644
--- a/apps/app_voicemail.c
+++ b/apps/app_voicemail.c
@@ -21,6 +21,10 @@
  * \brief Comedian Mail - Voicemail System
  *
  * \author Mark Spencer <markster@digium.com>
+ *
+ * \extref Unixodbc - http://www.unixodbc.org
+ * \extref A source distribution of University of Washington's IMAP
+c-client (http://www.washington.edu/imap/
  * 
  * \par See also
  * \arg \ref Config_vm
diff --git a/cdr/cdr_pgsql.c b/cdr/cdr_pgsql.c
index e8f5b73c1681444dec7b89dffcd5cbb196d9e3b6..34feca621093168b1cb4340cde6bd45d1ba7b7b2 100644
--- a/cdr/cdr_pgsql.c
+++ b/cdr/cdr_pgsql.c
@@ -25,6 +25,7 @@
  * \brief PostgreSQL CDR logger 
  * 
  * \author Matthew D. Hardeman <mhardemn@papersoft.com> 
+ * \extref PostgreSQL http://www.postgresql.org/
  *
  * See also
  * \arg \ref Config_cdr
diff --git a/cdr/cdr_radius.c b/cdr/cdr_radius.c
index 51563fabf538041c11e3274c5d6b3a0b307f44eb..e79fc01701438db2c183c7a632fad5d09ffb967e 100644
--- a/cdr/cdr_radius.c
+++ b/cdr/cdr_radius.c
@@ -20,6 +20,7 @@
  *
  * \brief RADIUS CDR Support
  * \author Philippe Sultan
+ * \extref FreeRadius http://www.freeradius.org/
  * 
  * \arg See also \ref AstCDR
  * \ingroup cdr_drivers
diff --git a/cdr/cdr_sqlite.c b/cdr/cdr_sqlite.c
index c56fd4d9cdb10cc477b42fa15a5826458331b4c3..bcc50aa0e865790d5b44c5ed281ed516358f8e33 100644
--- a/cdr/cdr_sqlite.c
+++ b/cdr/cdr_sqlite.c
@@ -22,6 +22,7 @@
  * \brief Store CDR records in a SQLite database.
  * 
  * \author Holger Schurig <hs4233@mail.mn-solutions.de>
+ * \extref SQLite http://www.sqlite.org/
  *
  * See also
  * \arg \ref Config_cdr
diff --git a/channels/chan_h323.c b/channels/chan_h323.c
index 58964ee79815384503e244d2c767e49a12cb80a8..8f9278cd8b9834d0732aa378a7fecbbfc00b861f 100644
--- a/channels/chan_h323.c
+++ b/channels/chan_h323.c
@@ -29,6 +29,7 @@
  *
  * \par See also
  * \arg Config_h323
+ * \extref OpenH323 http://www.openh323.org/
  *
  * \ingroup channel_drivers
  */
diff --git a/codecs/codec_speex.c b/codecs/codec_speex.c
index 6978184ae0df557730a06530060ba565572c88e1..7a66b459f973bac0ec7fa16c61a7531c8db06ca6 100644
--- a/codecs/codec_speex.c
+++ b/codecs/codec_speex.c
@@ -21,10 +21,13 @@
  *
  * \brief Translate between signed linear and Speex (Open Codec)
  *
- * http://www.speex.org
  * \note This work was motivated by Jeremy McNamara 
  * hacked to be configurable by anthm and bkw 9/28/2004
+ *
  * \ingroup codecs
+ *
+ * \extref The Speex library - http://www.speex.org
+ *
  */
 
 /*** MODULEINFO
diff --git a/contrib/asterisk-ng-doxygen b/contrib/asterisk-ng-doxygen
index 868258b1c8d7763b4f8762f746405b7a6d93f104..6186e2c724bede5f08d7f0a773fa722379e4eeb7 100644
--- a/contrib/asterisk-ng-doxygen
+++ b/contrib/asterisk-ng-doxygen
@@ -181,7 +181,7 @@ TAB_SIZE               = 3
 # will result in a user-defined paragraph with heading "Side Effects:". 
 # You can put \n's in the value part of an alias to insert newlines.
 
-ALIASES                = 
+ALIASES += "extref=\xrefitem extref \"ExtRef\" \"External references\""
 
 # Set the OPTIMIZE_OUTPUT_FOR_C tag to YES if your project consists of C 
 # sources only. Doxygen will then generate output that is more tailored for C. 
diff --git a/funcs/func_curl.c b/funcs/func_curl.c
index 55228e1ea8128c5ea76a314d6fb9991e0b853d92..f7b5ce75f96eb84bb431fb3d1847bb3337ecd2bb 100644
--- a/funcs/func_curl.c
+++ b/funcs/func_curl.c
@@ -24,6 +24,8 @@
  * \author Tilghman Lesher <curl-20050919@the-tilghman.com>
  *
  * \note Brian Wilkins <bwilkins@cfl.rr.com> (Added POST option) 
+ *
+ * \extref Depends on the CURL library  - http://curl.haxx.se/
  * 
  * \ingroup functions
  */
diff --git a/include/asterisk/jabber.h b/include/asterisk/jabber.h
index b1154cf56655d172a73367b9feb4ee160ce264c2..ee247d3e2a3827c34390e03214c68b071aaccc62 100644
--- a/include/asterisk/jabber.h
+++ b/include/asterisk/jabber.h
@@ -21,6 +21,7 @@
  * \ref AJI_intro
  * \ref res_jabber.c
  * \author Matt O'Gorman <mogorman@digium.com>
+ * \extref IKSEMEL http://iksemel.jabberstudio.org
  *
  * \page AJI_intro AJI - The Asterisk Jabber Interface
  * 
diff --git a/res/res_crypto.c b/res/res_crypto.c
index 888564ea872427990e67d838b7d6fb4a2ee606d4..4e4a363e1111111847af96ce109e64a92f6b2b2a 100644
--- a/res/res_crypto.c
+++ b/res/res_crypto.c
@@ -21,6 +21,9 @@
  * \brief Provide Cryptographic Signature capability
  *
  * \author Mark Spencer <markster@digium.com> 
+ *
+ * \extref Uses the OpenSSL library, available at
+ *	http://www.openssl.org/
  */
 
 /*** MODULEINFO
diff --git a/res/res_snmp.c b/res/res_snmp.c
index cbca08a4199605525db3f4fcf39dfdc4165b86dc..b4a9e0fca9b3ab210a63864762c7528a30951d04 100644
--- a/res/res_snmp.c
+++ b/res/res_snmp.c
@@ -12,6 +12,9 @@
  * \brief SNMP Agent / SubAgent support for Asterisk
  *
  * \author Thorsten Lockert <tholo@voop.as>
+ *
+ * \extref Uses the Net-SNMP libraries available at
+ *	 http://net-snmp.sourceforge.net/
  */
 
 /*** MODULEINFO