How to use xpath when the xml contains namespaces ?

[bouillons]

I have an xml that contains namespaces and prefixes. I'd like to extract data from it using an xpath. When I try my xpath statement on the same xml from which I removed all namespaces and prefixes it works. Where can I find more information on the proper use and syntax for this scenario ?

This works:

xpath(outputs('Compose_Points_of_Sales_as_xml'),'string(/list/item[starts-with(POSNr,"0002")]/Location)')

This doesn't work:

xpath(outputs('Compose_Points_of_Sales_as_xml'),'string(/d:list/d:item[starts-with(d:POSNr,"0002")]/d:Location)')

Stephane