diff --git a/doc/docbook.sh b/doc/docbook.sh
index 4ac88b6..fda4e2d 100755
--- a/doc/docbook.sh
+++ b/doc/docbook.sh
@@ -27,6 +27,7 @@
 #variables
 PREFIX="/usr/local"
 [ -f "../config.sh" ] && . "../config.sh"
+PROGNAME="docbook.sh"
 #executables
 DEBUG="_debug"
 FOP="fop"
@@ -51,19 +52,25 @@ _docbook()
 {
 	target="$1"
 
-	source="${target#$OBJDIR}"
-	source="${source%.*}.xml"
+	source="${target%.*}.xml"
+	[ -f "$source" ] || source="${source#$OBJDIR}"
 	ext="${target##*.}"
 	ext="${ext##.}"
 	case "$ext" in
 		html)
 			XSL="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"
+			[ -f "${source%.*}.xsl" ] && XSL="${source%.*}.xsl"
 			[ -f "${target%.*}.xsl" ] && XSL="${target%.*}.xsl"
-			[ -f "${target%.*}.css.xml" ] && XSLTPROC="$XSLTPROC --param custom.css.source \"${target%.*}.css.xml\" --param generate.css.header 1"
+			if [ -f "${target%.*}.css.xml" ]; then
+				XSLTPROC="$XSLTPROC --param custom.css.source \"${target%.*}.css.xml\" --param generate.css.header 1"
+			elif [ -f "${source%.*}.css.xml" ]; then
+				XSLTPROC="$XSLTPROC --param custom.css.source \"${source%.*}.css.xml\" --param generate.css.header 1"
+			fi
 			$DEBUG $XSLTPROC -o "$target" "$XSL" "$source"
 			;;
 		pdf)
 			XSL="http://docbook.sourceforge.net/release/xsl/current/fo/docbook.xsl"
+			[ -f "${source%.*}.xsl" ] && XSL="${source%.*}.xsl"
 			[ -f "${target%.*}.xsl" ] && XSL="${target%.*}.xsl"
 			$DEBUG $XSLTPROC -o "${target%.*}.fo" "$XSL" "$source" &&
 			$DEBUG $FOP -fo "${target%.*}.fo" -pdf "$target"
@@ -74,13 +81,13 @@ _docbook()
 			$DEBUG $XSLTPROC -o "$target" "$XSL" "$source"
 			;;
 		*)
-			echo "$0: $target: Unknown type" 1>&2
+			_error "$target: Unknown type"
 			return 2
 			;;
 	esac
 
 	if [ $? -ne 0 ]; then
-		echo "$0: $target: Could not create page" 1>&2
+		_error "$target: Could not create page"
 		$RM -- "$target"
 		return 2
 	fi
@@ -90,7 +97,7 @@ _docbook()
 #error
 _error()
 {
-	echo "docbook.sh: $@" 1>&2
+	echo "$PROGNAME: $@" 1>&2
 	return 2
 }
 
@@ -98,7 +105,7 @@ _error()
 #usage
 _usage()
 {
-	echo "Usage: docbook.sh [-c|-i|-u][-P prefix] target..." 1>&2
+	echo "Usage: $PROGNAME [-c|-i|-u][-P prefix] target..." 1>&2
 	return 1
 }
 
@@ -169,7 +176,7 @@ while [ $# -gt 0 ]; do
 			instdir="$MANDIR/man$ext"
 			;;
 		*)
-			echo "$0: $target: Unknown type" 1>&2
+			_error "$target: Unknown type"
 			exit 2
 			;;
 	esac