def parse_journal(response, paper_id):
    """Parse journal information from a MAG API response.
    
    Args:
        response (json): Response from MAG API in JSON format. Contains all paper information.
        paper_id (int): Paper ID.

    Returns:
        d (dict): Journal details.

    """
    return {
        "id": response["J"]["JId"],
        "journal_name": response["J"]["JN"],
        "paper_id": paper_id,
    }