Generic Formulation - Azithromycin 250mg oral capsule - includes a reference to a substance in the Ingredient element

{
  "resourceType" : "Medication",
  "id" : "med0320",
  "text" : {
    "status" : "generated",
    "div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\"><p><b>Generated Narrative: Medication</b><a name=\"med0320\"> </a></p><div style=\"display: inline-block; background-color: #d9e0e7; padding: 6px; margin: 4px; border: 1px solid #8da1b4; border-radius: 5px; line-height: 60%\"><p style=\"margin-bottom: 0px\">Resource Medication &quot;med0320&quot; </p></div><p><b>code</b>: Azithromycin 250mg capsule (product) <span style=\"background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki\"> (<a href=\"https://browser.ihtsdotools.org/\">SNOMED CT</a>#324252006)</span></p><p><b>doseForm</b>: Tablet dose form (qualifier value) <span style=\"background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki\"> (<a href=\"https://browser.ihtsdotools.org/\">SNOMED CT</a>#385055001)</span></p><blockquote><p><b>ingredient</b></p><h3>Items</h3><table class=\"grid\"><tr><td>-</td><td><b>Reference</b></td></tr><tr><td>*</td><td><a name=\"sub03\"> </a><blockquote><p/><p><a name=\"sub03\"> </a></p><p><b>instance</b>: false</p><h3>Codes</h3><table class=\"grid\"><tr><td>-</td><td><b>Concept</b></td></tr><tr><td>*</td><td>Azithromycin (substance) <span style=\"background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki\"> (<a href=\"https://browser.ihtsdotools.org/\">SNOMED CT</a>#387531004)</span></td></tr></table></blockquote></td></tr></table><p><b>strength</b>: 250 mg<span style=\"background: LightGoldenRodYellow\"> (Details: UCUM code mg = 'mg')</span>/1(unit TAB from http://terminology.hl7.org/CodeSystem/v3-orderableDrugForm)<span style=\"background: LightGoldenRodYellow\"> (Details: http://terminology.hl7.org/CodeSystem/v3-orderableDrugForm code TAB = 'Tablet')</span></p></blockquote></div>"
  },
  "contained" : [{
    "resourceType" : "Substance",
    "id" : "sub03",
    "instance" : false,
    "code" : {
      "concept" : {
        "coding" : [{
          "system" : "http://snomed.info/sct",
          "code" : "387531004",
          "display" : "Azithromycin (substance)"
        }]
      }
    }
  }],
  "code" : {
    "coding" : [{
      "system" : "http://snomed.info/sct",
      "code" : "324252006",
      "display" : "Azithromycin 250mg capsule (product)"
    }]
  },
  "doseForm" : {
    "coding" : [{
      "system" : "http://snomed.info/sct",
      "code" : "385055001",
      "display" : "Tablet dose form (qualifier value)"
    }]
  },
  "ingredient" : [{
    "item" : {
      "reference" : {
        "reference" : "#sub03"
      }
    },
    "strengthRatio" : {
      "numerator" : {
        "value" : 250,
        "system" : "http://unitsofmeasure.org",
        "code" : "mg"
      },
      "denominator" : {
        "value" : 1,
        "system" : "http://terminology.hl7.org/CodeSystem/v3-orderableDrugForm",
        "code" : "TAB"
      }
    }
  }]
}