{
    "$schema":"http://json-schema.org/draft-04/schema#",
    "$ref":"#/definitions/MyObject",
    "definitions":{
        "MyObject":{
            "type":"object",
            "properties":{
                "propA":{"type":"number"},
                "propB":{"$ref": "#/definitions/MyObject"}
            },
            "required": [
                "propA",
                "propB"
            ]
        }
    }
}