RE: multiple files to single file problem

> 	<xsl:template match="/" name="main">
> 		<xsl:element name="cover-body">

It's so much clearer if you use literal result elements: <cover-body>
instead of <xsl:element name="cover-body">.

> 			<xsl:for-each select="for $x in 
> collection('file:///D:/cover/sample
> xmls/pageall/else/nima?select=*.xml;recurse=yes;on-error=ignore')
> return $x">

The XPath expression "for $x in EXPR return $x" can always be rewritten
"EXPR". You just want

<xsl:for-each select="collection(....)">

> 				<xsl:variable name="a" 
> select="document(document-uri(/))"/>

That's equivalent to <xsl:variable name="a" select="."/>

> 		<xsl:element name="author">
> 							
> <xsl:value-of 
> select="$a/article/head/author-group/author/given-name"/>
> 							<xsl:text/>
> 							
> <xsl:value-of select="$a/article/head/author-group/author/surname"/>
> 						</xsl:element>
> 					</xsl:element>

xsl:value-of takes the selected nodes (all the given-names) and outputs
their values, space-separated. So you have asked for all the given-names,
space-separated, then all the surnames, space-separated. What you want is
this:

<author>
  <xsl:for-each select="$a/article/head/author-group/author">
    <xsl:value-of select="given-name, surname"/>
  </xsl:for-each>
</author>

perhaps with some added punctuation or markup.

Michael Kay
http://www.saxonica.com/