1. Sorrell v. Smith [1925] A.C. 700, 713 per Viscount Cave L.C.
2. Pratt v. British Medical Association;McCardie;K.B.,1919
3. Lumley v. Gye (1853) 2 E.& B. 216, 230 per Crompton J. , 234 per Erie J
4. Sorrell v. Smith [1925] A.C. 700, 713 per Viscount CaveL.C. , p. 740 per Lord Sumner
5. Derby & Co. v. Weldon (No. 5) [1989] 1 W.L.R. 1244 at 1254