diff --git a/docs/howto/outputting-pdf.txt b/docs/howto/outputting-pdf.txt
index 31ed83fa84..7bcd5ccdd4 100644
--- a/docs/howto/outputting-pdf.txt
+++ b/docs/howto/outputting-pdf.txt
@@ -155,7 +155,7 @@ Further resources
 
 .. _PDFlib: http://www.pdflib.org/
 .. _`Pisa XHTML2PDF`: http://www.xhtml2pdf.com/
-.. _HTMLdoc: http://www.htmldoc.org/
+.. _HTMLdoc: https://www.msweet.org/projects.php?Z1
 
 Other formats
 =============