(orders
    # DOC:ORDER1
    (order id=1
        (lineitem product-id=123, quantity=1, item-price=99.90)
        (lineitem product-id=456, quantity=2, item-price=12.29)
        (lineitem product-id=888, quantity=1, item-price=1.99)
    )
    # DOC:ORDER1
    (order id=2
        (lineitem product-id=777, quantity=2, item-price=10.00)
    )
)