Media type:
application/json; schema=dublin_core
Null data URI with this type:
data:application/json;schema=dublin_core,%7B%7D
Link response header with null data URI:
Link: data:application/json;schema=dublin_core,%7B%7D; rel="meta"
Link response header with artist and song title:
data:application/json; schema=dublin_core,{Creator%3A"Michael%20Jackson"%2CTitle%3D"Billie%20Jean"}
Using a data URI instead an HTTP URI is more robust, simpler and faster. I had to invent the media type, though. application/json; schema=dublin_core is a neologism.
Also, having two semicolons in there (you need one for the media type parameter to the data URI and one for the rel attribute) might be a bug.