bug#64766: [PATCH] doc: Fix broken URLs in some documents.

* doc/ref/scheme-reading.texi: Fix all URLs.
* doc/ref/slib.texi: Fix the URL of `JACAL'.
---
 doc/ref/scheme-reading.texi | 14 +++++++-------
 doc/ref/slib.texi           |  4 ++--
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/doc/ref/scheme-reading.texi b/doc/ref/scheme-reading.texi
index f147ea00d..b7a35b73d 100644
--- a/doc/ref/scheme-reading.texi
+++ b/doc/ref/scheme-reading.texi
@@ -1,6 +1,6 @@
 @c -*-texinfo-*-
 @c This is part of the GNU Guile Reference Manual.
-@c Copyright (C)  1996, 1997, 2000, 2001, 2002, 2003, 2004, 2011
+@c Copyright (C)  1996, 1997, 2000, 2001, 2002, 2003, 2004, 2011, 2023
 @c   Free Software Foundation, Inc.
 @c See the file guile.texi for copying conditions.
 
@@ -10,22 +10,22 @@
 @itemize @bullet
 
 @item
-The website @url{http://www.schemers.org/} is a good starting point for
+The website @url{https://www.scheme.org/} is a good starting point for
 all things Scheme.
 
 @item
 Dorai Sitaram's online Scheme tutorial, @dfn{Teach Yourself Scheme in
-Fixnum Days}, at
-@url{http://www.ccs.neu.edu/home/dorai/t-y-scheme/t-y-scheme.html}.
+Fixnum Days}, at @url{https://ds26gte.github.io/tyscheme/index.html}.
 Includes a nice explanation of continuations.
 
 @item
 The complete text of @dfn{Structure and Interpretation of Computer
 Programs}, the classic introduction to computer science and Scheme by
 Hal Abelson, Jerry Sussman and Julie Sussman, is now available online at
-@url{http://mitpress.mit.edu/sicp/sicp.html}.  This site also provides
-teaching materials related to the book, and all the source code used in
-the book, in a form suitable for loading and running.
+@url{https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/index.html}.
+This site also provides teaching materials related to the book, and all
+the source code used in the book, in a form suitable for loading and
+running.
 @end itemize
 
 
diff --git a/doc/ref/slib.texi b/doc/ref/slib.texi
index 388dae1f6..c76bc3744 100644
--- a/doc/ref/slib.texi
+++ b/doc/ref/slib.texi
@@ -119,8 +119,8 @@ You can use Guile's interface to SLIB to invoke Jacal:
 @noindent
 For complete documentation on Jacal, please read the Jacal manual.  If
 it has been installed on line, you can look at @ref{Top, , Jacal, jacal,
-JACAL Symbolic Mathematics System}.  Otherwise you can find it on the web at
-@url{http://www-swiss.ai.mit.edu/~jaffer/JACAL.html}
+JACAL Symbolic Mathematics System}.  Otherwise you can find it on the
+web at @url{http://people.csail.mit.edu/jaffer/JACAL.html}
 
 
 @c Local Variables:

base-commit: 0e9ccaf47cb956f70c8ecd4b9fba64fea4023dfc
-- 
2.41.0