{
  "swagger": "2.0",
  "info": {
    "title": "a $ref under a keyword this model does not map",
    "version": "1.0.0"
  },
  "paths": {
    "/things": {
      "get": {
        "responses": {
          "200": {
            "description": "a thing",
            "schema": {
              "$ref": "#/definitions/holder"
            }
          }
        }
      }
    }
  },
  "definitions": {
    "holder": {
      "$ref": "other.json#/definitions/deep"
    }
  }
}