Decoupling between Link and its mediatype, and inputData/outputData

Dear all,

The decoupling between Link and its mediatype, and inputData/outputData,
makes me having some trouble trying to model the following situation:

Suppose a device exposes the same information in xml or json, using
content-negotiation, at http://192.168.0.10/property
 - the xml version has a canonical URL  http://192.168.0.10/property.xml (see
also Content-Location)
 - the json version has a canonical URL http://192.168.0.10/property.json

I'd like to model this situation with a single device, a single
td:Property, three td:Link, and only two td:DataSchema objects.

How do you suggest to manage this ?

Best,
Maxime Lefrançois