Cox, Russell J.; O'Hagan, David
Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1991 , # 10 p. 2537 - 2540
Ashworth, Doreen M.; Robinson, John A.; Turner, David L.
Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1988 , p. 1719 - 1728