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Help with Linking RQM testcases to requirements using REST Client

Accepted answer

The URL to the requirement is just the "permalink" to the requirement aritfact.
https://jazz.net/downloads/rational-requirements-composer/releases/4.0?p=news#usab-1
Normally you would do a PUT to modify an existing test artifact, not use POST to create a new test artifact. In this case, you can do a GET first to retrieve the XML data of the test artifact and make appropriate changes on top of it. For more details, check the RQM REST API Wiki.
https://jazz.net/wiki/bin/view/Main/RqmApi