Provenance holding a signature

{
  "resourceType": "Provenance",
  "id": "signature",
  "text": {
    "status": "generated",
    "div": "<div xmlns=\"http://www.w3.org/1999/xhtml\">procedure record authored on 27-June 2015 by Harold Hippocrates, MD Content extracted from Referral received 26-June</div>"
  },
  "target": [
    {
      "reference": "DocumentReference/example"
    }
  ],
  "recorded": "2015-08-27T08:39:24+10:00",
  "reason": [
    {
      "coding": [
        {
          "system": "http://terminology.hl7.org/CodeSystem/v3-ActReason",
          "code": "TREAT",
          "display": "treatment"
        }
      ]

  "resourceType" : "Provenance",
  "id" : "signature",
  "target" : [{
    "reference" : "DocumentReference/example/_history/4"
  }],
  "recorded" : "2015-08-27T08:39:24+10:00",
  "authorization" : [{
    "concept" : {
      "coding" : [{
        "system" : "http://terminology.hl7.org/CodeSystem/v3-ActReason",
        "code" : "TREAT",
        "display" : "treatment"
      }]

    }
  ],
  "activity": {
    "coding": [
      {
        "system": "http://terminology.hl7.org/CodeSystem/v3-DocumentCompletion",
        "code": "AU",
        "display": "authenticated"
      }
    ]

  }],
  "activity" : {
    "coding" : [{
      "system" : "http://terminology.hl7.org/CodeSystem/v3-DocumentCompletion",
      "code" : "AU",
      "display" : "authenticated"
    }]

  },
  "agent": [
    {
      "type": {
        "coding": [
          {
            "system": "http://terminology.hl7.org/CodeSystem/contractsignertypecodes",
            "code": "VERF"
          }
        ]
      },
      "who": {
        "identifier": {
          "system": "urn:ietf:rfc:3986",
          "value": "mailto://hhd@ssa.gov"
        }

  "agent" : [{
    "type" : {
      "coding" : [{
        "system" : "http://terminology.hl7.org/CodeSystem/contractsignertypecodes",
        "code" : "VERF"
      }]
    },
    "who" : {
      "identifier" : {
        "system" : "urn:ietf:rfc:3986",
        "value" : "mailto://hhd@ssa.gov"

      }
    }
  ],
  "signature": [
    {
      "type": [
        {
          "system": "urn:iso-astm:E1762-95:2013",
          "code": "1.2.840.10065.1.12.1.5",
          "display": "Verification Signature"
        }
      ],
      "when": "2015-08-27T08:39:24+10:00",
      "who": {
        "reference": "Practitioner/xcda-author"
      },
      "targetFormat": "application/fhir+xml",
      "sigFormat": "application/signature+xml",
      "data": "Li4u"
    }
  ]

  }],
  "signature" : [{
    "type" : [{
      "system" : "urn:iso-astm:E1762-95:2013",
      "code" : "1.2.840.10065.1.12.1.5",
      "display" : "Verification Signature"
    }],
    "when" : "2015-08-27T08:39:24+10:00",
    "who" : {
      "reference" : "Practitioner/xcda-author"
    },
    "targetFormat" : "application/fhir+xml",
    "sigFormat" : "application/signature+xml",
    "data" : "Li4u"
  }]

}