[1] UNIV CAPE TOWN,DEPT CHEM PATHOL,MRC,BIOMEMBRANE RES UNIT,ZA-7925 RONDEBOSCH,SOUTH AFRICA
[2] UNIV ESSEX,DEPT BIOL & CHEM SCI,COLCHESTER CO4 3SQ,ESSEX,ENGLAND
[3] RED CROSS WAR MEM CHILDRENS HOSP,DEPT CHEM PATHOL,INST CHILD HLTH,ZA-7700 RONDEBOSCH,SOUTH AFRICA