diff --git a/doc/Makefile.am b/doc/Makefile.am
index 2032420..c6b753a 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -20,31 +20,29 @@
 SUBDIRS = reference
 endif
 
-EXTRA_DIST = gdoc TODO libtasn1.html libtasn1.ps libtasn1.pdf stamp_docs \
-	COPYING COPYING.LESSER
+EXTRA_DIST = gdoc TODO stamp_docs COPYING COPYING.LESSER
 
 info_TEXINFOS = libtasn1.texi
-libtasn1_TEXINFOS = fdl-1.3.texi texinfo.css $(gdoc_TEXINFOS)
+libtasn1_TEXINFOS = fdl-1.3.texi $(gdoc_TEXINFOS)
 
-AM_MAKEINFOHTMLFLAGS = $(AM_MAKEINFOFLAGS) \
-	--no-split --number-sections --css-include=texinfo.css
+AM_MAKEINFOHTMLFLAGS = --no-split $(AM_MAKEINFOFLAGS)
 
 dist_man_MANS = $(gdoc_MANS) asn1Parser.1 asn1Coding.1 asn1Decoding.1
 
 HELP2MAN_OPTS = --info-page libtasn1
 
-asn1Parser.1: $(top_srcdir)/src/asn1Parser.c $(top_srcdir)/configure.ac
-	$(HELP2MAN) $(HELP2MAN_OPTS) \
+asn1Parser.1: $(top_srcdir)/src/asn1Parser.c $(top_srcdir)/.version
+	$(AM_V_GEN)$(HELP2MAN) $(HELP2MAN_OPTS) \
 		--name="ASN.1 syntax tree generator for libtasn1" \
 		--output=$@ $(top_builddir)/src/asn1Parser$(EXEEXT)
 
-asn1Coding.1: $(top_srcdir)/src/asn1Coding.c $(top_srcdir)/configure.ac
-	$(HELP2MAN) $(HELP2MAN_OPTS) \
+asn1Coding.1: $(top_srcdir)/src/asn1Coding.c $(top_srcdir)/.version
+	$(AM_V_GEN)$(HELP2MAN) $(HELP2MAN_OPTS) \
 		--name="ASN.1 DER encoder" \
 		--output=$@ $(top_builddir)/src/asn1Coding$(EXEEXT)
 
-asn1Decoding.1: $(top_srcdir)/src/asn1Decoding.c $(top_srcdir)/configure.ac
-	$(HELP2MAN) $(HELP2MAN_OPTS) \
+asn1Decoding.1: $(top_srcdir)/src/asn1Decoding.c $(top_srcdir)/.version
+	$(AM_V_GEN)$(HELP2MAN) $(HELP2MAN_OPTS) \
 		--name="ASN.1 DER decoder" \
 		--output=$@ $(top_builddir)/src/asn1Decoding$(EXEEXT)
 
@@ -172,7 +170,7 @@
 clean-local:
 	-rm -f stamp_docs
 
-stamp_docs:
+stamp_docs: $(top_srcdir)/.version
 	$(mkdir_p) man texi; \
 	for i in `$(srcdir)/gdoc -listfunc $(GDOC_SRC)`; do \
 		echo -n "Creating documentation for $$i... " && \
diff --git a/doc/gdoc b/doc/gdoc
index e3db762..d109399 100755
--- a/doc/gdoc
+++ b/doc/gdoc
@@ -1,8 +1,8 @@
-eval '(exit $?0)' && eval 'exec perl "$0" ${1+"$@"}'
-  & eval 'exec perl "$0" $argv:q'
+eval '(exit $?0)' && eval 'exec perl -S "$0" ${1+"$@"}'
+    & eval 'exec perl -S "$0" $argv:q'
     if 0;
 
-## Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Simon Josefsson
+## Copyright (c) 2002-2021 Simon Josefsson
 ##                    added -texinfo, -listfunc, -pkg-name
 ##                    man page revamp
 ##                    various improvements
@@ -104,14 +104,14 @@
 #  * my_function - does my stuff
 #  * @my_arg: its mine damnit
 #  *
-#  * Does my stuff explained. 
+#  * Does my stuff explained.
 #  */
 #
 #  or, could also use:
 # /**
 #  * my_function - does my stuff
 #  * @my_arg: its mine damnit
-#  * Description: Does my stuff explained. 
+#  * Description: Does my stuff explained.
 #  */
 # etc.
 #
@@ -303,7 +303,7 @@
 #  parameters => %parameter descriptions
 #  sectionlist => @list of sections
 #  sections => %descriont descriptions
-#  
+#
 
 sub just_highlight {
     my $contents = join "\n", @_;
@@ -1062,7 +1062,7 @@
 
 		$state = 0;
 	    }
-    
+
 	}
     }