Re: return type of a function returning namespaces?

Thank you Michael!

Is there a similar central reference for where the xs:<type> types (xs:string,
xs:integer, etc.) are defined?

I know these are RTFM questions, but I've made multiple honest efforts to
locate this information, and I'm just not familiar enough with the terminology
to find it. I'm basically looking to bookmark whatever information I should
reference when I'm writing an XSLT stylesheet and I need to write

	as="thingy()"
	as="xs:thingy"

 - Chris