If you create two content references or with the exact same URL, the second one fails.
For example, suppose you create an external content reference with a URL of www.example.com. Then you create a second content reference that has a node of PeopleSoft, whose URI is www.example.com. The creation of the second content reference fails because the URL already exists.
If you have multiple nodes with the same URI, FindCRefByURL looks for the specified content reference with all those nodes.
If you have multiple nodes with the same URI, but no registered content references, the system uses the template from the alphabetically first node it finds.
Pagelet, node, and portal registry names can consist of any combination of letters, digits and underscores, but they must not contain any spaces or begin with a digit.
Content reference link names cannot have start with numbers, and can not have special characters and spaces.