diff --git a/doc/manual/Makefile b/doc/manual/Makefile
index 8e5e1f0bce..95b472eee5 100644
--- a/doc/manual/Makefile
+++ b/doc/manual/Makefile
@@ -1,3 +1,10 @@
 DOCBOOK_DTD = /nix/current/xml/dtd/docbook
 DOCBOOK_XSL  =/nix/current/xml/xsl/docbook/
 
+check:
+	SP_CHARSET_FIXED=YES SP_ENCODING=XML \
+	nsgmls -wxml -c /usr/share/sgml/opensp/xml.soc -c $(DOCBOOK_DTD)/docbook.cat -ges book.xml
+
+html:
+	mkdir -p out
+	xsltproc --output out/book.html $(DOCBOOK_XSL)/html/docbook.xsl book.xml