David A Richards, Joan Meakins, Jane Tawfik, Lesley Godfrey, Evelyn Dutton, Gerald Richardson et al
Richards D A, Meakins J, Tawfik J, Godfrey L, Dutton E, Richardson G et al.
Nurse telephone triage for same day appointments in general practice: multiple interrupted time series trial of effect on workload and costs
BMJ 2002; 325 :1214
doi:10.1136/bmj.325.7374.1214