curl -X GET "https://api.globalwebindex.com/v2/categories/520?include=children" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "category": {
    "id": "520",
    "name": "Social and Messaging Usage",
    "child_questions": [
      {
        "code": "q42011",
        "name": "Named social media services used Q4 2011",
        "namespace_code": "core",
        "description": "Which social media platforms do you use?"
      }
    ]
  }
}
Now, retrieve all questions within the Social and Messaging Usage subcategory. 
curl -X GET "https://api.globalwebindex.com/v2/categories/520?include=children" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "category": {
    "id": "520",
    "name": "Social and Messaging Usage",
    "child_questions": [
      {
        "code": "q42011",
        "name": "Named social media services used Q4 2011",
        "namespace_code": "core",
        "description": "Which social media platforms do you use?"
      }
    ]
  }
}
From the response, note the question’s unique identifier: core.q42011.