diff --git a/apps/app_festival.c b/apps/app_festival.c
index 1fa935e0b1..678b8cd860 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 3adde50f2f..6ac6682609 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 f06c9dacc5..5cb03c86ae 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 e8f5b73c16..34feca6210 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 51563fabf5..e79fc01701 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 c56fd4d9cd..bcc50aa0e8 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 58964ee798..8f9278cd8b 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 6978184ae0..7a66b459f9 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 868258b1c8..6186e2c724 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 55228e1ea8..f7b5ce75f9 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 b1154cf566..ee247d3e2a 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 888564ea87..4e4a363e11 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 cbca08a419..b4a9e0fca9 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