{
  "prefix": {
    "ex": "http://example.org/"
  },
  "wasDerivedFrom": {
    "ex:der6": {
      "prov:activity": "ex:a",
      "prov:generatedEntity": "ex:e2",
      "prov:usage": "ex:u",
      "prov:usedEntity": "ex:e1"
    }
  }
}