RT Journal Article SR Electronic T1 The laws of Murfitt JF Archives of Disease in Childhood JO Arch Dis Child FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP 818 OP 819 DO 10.1136/adc.61.8.818 VO 61 IS 8 A1 A Nicoll YR 1986 UL http://adc.bmj.com/content/61/8/818.abstract AB