entrees/What is genetic modification? What are GMOs?. Pandora's Picnic Basket. Oxford University Press. 2000-09-14. ISBN 978-0198506744. Staff (28 November
318–319, 375–377, and 416頁) Trockel (1984,第30頁): Trockel, Walter. Market demand: An analysis of large economies with nonconvex preferences [市場需求:分析非凸偏好的大經濟體]