{
  "top-cont": {
    "keyed-list":[
      {
        "identityref-key-leaf": "derived-id",
        "regular-leaf": 150
      }
    ],

    "iid-leaf": "/zab:top-cont/zab:keyed-list[zab:identityref-key-leaf='derived-id']/zab:regular-leaf"
  }
}