How to insert in XSLT
Use the entity code   instead.
is a HTML "character entity reference". There is no named entity for non-breaking space in XML, so you use the code  .
Wikipedia includes a list of XML and HTML entities, and you can see that there are only 5 "predefined entities" in XML, but HTML has over 200. I'll also point over to Creating a space ( ) in XSL which has excellent answers.
  works really well. However, it will display one of those strange characters in ANSI encoding. <xsl:text> worked best for me.
<xsl:text> </xsl:text>
One can also do this :
<xsl:text disable-output-escaping="yes"><![CDATA[ ]]></xsl:text>