Letter from Howard Walter Florey to Dr Brunton, Pfizer and Company Limited, Folkestone Says people in department, who are working on problem of what cells do to cholesterol esters, which to determine difference between esters of cholesterol with saturated and unsaturated fatty acids - asks if Brunton could supply samples of cholesteryl linoleate or mixture of polyunsaturated fatty acids esters of cholesterol - comments on this. 13 June 1958