[1] X Sharp/Nodes ( 版) <http://wiki.codeglide.com/X_Sharp/Nodes#Selecting_nodes>
XPath expressions can be used within the <?xpath ?> instruction to select and pass nodes to the current output collection, for example:
<!-- Add to the output collection only books with prices under $50 --> <?xpath $library/book[@price < 50] ?>
[2] XPointer Registry ( ( 版)) <http://www.w3.org/2005/04/xpointer-schemes/xpath>
[3] public-xpointer-registry@w3.org from January to March 2011 by thread ( ( 版)) <http://lists.w3.org/Archives/Public/public-xpointer-registry/2011JanMar/thread.html>