Linking to another chunked topic

Hey folks.

I have the following bit of structure:

Top Topic chunk=to-content

--Subtopic A

--Subtopic B 

--Subtopic C

Subtopics B and C are reference topics, and I want to link to them from the relevant point in Subtopic A. 

I think that I can link <xref href="#top-topic-id/subtopic-B-id>, because at publishing the page id will be the top topic id? Focus Areas: BPEL | DITA | ebXML | IDtrust | OpenDocument | SAML | UBL | UDDI
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