make the use of the 5-argument @xref command consistent

A few of the @xref references to external manuals in the documentation
are using an old 4-argument form that produces an undefined reference
in the printed manual.  The following patch makes them consistent with
the 5-argument @xrefs used elsewhere in the manual.

--
Brian Gough

Network Theory Ltd,
Publishing Free Software Manuals --- http://www.network-theory.co.uk/

>From 6ca0417830dc5a98699a15808591dc1f2a90dfac Mon Sep 17 00:00:00 2001
From: Brian Gough <bjg@gnu.org>
Date: Mon, 14 Dec 2009 21:34:59 +0000
Subject: [PATCH] make the use of the 5-argument @xref command consistent
 when referring to other manuals.

3 files changed, 15 insertions, 13 deletions

diff --git a/doc/ref/autoconf.texi b/doc/ref/autoconf.texi
index ae807c276..1e334c0d1 100644
--- a/doc/ref/autoconf.texi
+++ b/doc/ref/autoconf.texi
@@ -11,7 +11,6 @@
 When Guile is installed, a pkg-config description file and a set of
 Autoconf macros is installed.  This chapter documents pkg-config and
 Autoconf support, as well as the high-level guile-tool Autofrisk.
-@xref{Top,The GNU Autoconf Manual,,autoconf}, for more info.
 
 @menu
 * Autoconf Background::         Why use autoconf?
@@ -25,19 +24,21 @@ Autoconf support, as well as the high-level guile-tool Autofrisk.
 @node Autoconf Background
 @section Autoconf Background
 
-As explained elsewhere (@pxref{Top,The GNU Autoconf Manual,,autoconf}), any
-package needs configuration at build-time.  If your package uses Guile (or
-uses a package that in turn uses Guile), you probably need to know what
-specific Guile features are available and details about them.
+As explained in the @cite{GNU Autoconf Manual}, any package needs
+configuration at build-time (@pxref{Top, ,Introduction,autoconf,The GNU
+Autoconf Manual}).  If your package uses Guile (or uses a package that
+in turn uses Guile), you probably need to know what specific Guile
+features are available and details about them.
 
 The way to do this is to write feature tests and arrange for their execution
 by the @file{configure} script, typically by adding the tests to
 @file{configure.ac}, and running @code{autoconf} to create @file{configure}.
 Users of your package then run @file{configure} in the normal way.
 
-Macros are a way to make common feature tests easy to express.  Autoconf
-provides a wide range of macros (@pxref{Existing Tests,,,autoconf}), and
-Guile installation provides Guile-specific tests in the areas of:
+Macros are a way to make common feature tests easy to express.
+Autoconf provides a wide range of macros 
+(@pxref{Existing Tests,,,autoconf,The GNU Autoconf Manual}), 
+and Guile installation provides Guile-specific tests in the areas of:
 program detection, compilation flags reporting, and Scheme module
 checks.
 
diff --git a/doc/ref/scheme-ideas.texi b/doc/ref/scheme-ideas.texi
index 55093cf92..e9b776500 100644
--- a/doc/ref/scheme-ideas.texi
+++ b/doc/ref/scheme-ideas.texi
@@ -549,9 +549,10 @@ and then by describing the value and side effects of evaluation for each
 type of expression individually.
 
 @noindent
-So, some@footnote{These definitions are approximate.  For the whole and
-detailed truth, see @xref{Formal syntax and semantics,R5RS
-syntax,,r5rs}.} definitions@dots{}
+So, some@footnote{These definitions are approximate.  For the whole
+and detailed truth, see @ref{Formal syntax and semantics,R5RS
+syntax,,r5rs,The Revised(5) Report on the Algorithmic Language
+Scheme}.} definitions@dots{}
 
 @itemize @bullet
 
diff --git a/doc/ref/scheme-intro.texi b/doc/ref/scheme-intro.texi
index e3542d8a1..f8852d3dc 100644
--- a/doc/ref/scheme-intro.texi
+++ b/doc/ref/scheme-intro.texi
@@ -15,8 +15,8 @@ series of reports known as @dfn{RnRS}.  @dfn{RnRS} is shorthand for the
 @ifnottex
 @dfn{Revised^n Report on the Algorithmic Language Scheme}.
 @end ifnottex
-The current latest revision of RnRS is version 5
-(@pxref{Top,R5RS,,r5rs}), and Guile 1.4 is fully compliant with the
+The current latest revision of RnRS is version 5 (@pxref{Top,
+,Introduction,r5rs,R5RS}), and Guile 1.4 is fully compliant with the
 Scheme specification in this revision.
 
 But Guile, like most Scheme implementations, also goes beyond R5RS in