6Hardy D J, O'Brien A P, Gaskin C J, et al. Practi- cal application of the Delphi technique in a bicullural mental health nursing study in New Zealand[J].Journal of Advanced Nursing, 2004, 46 ( 1 ): 95-109.
7Cristobal V, Carol J, Cardona B, et al. Simulation of an early warning system using sentinel birds to detect a change of a low pathogenic avian influenza virus (LPA1V) to high patho- genic avian influenza virus (HPAIV)[J].Preventive Veterinary Medicine, 2008,88(2 ): 109-119.
8Daniel B A, Carpenter T E, Carol C, et al. A flock-tailored early warning system for low pathogenic avian influenza(LPA1) in commercial egg laying flocks[J].Preventive Veterinary Medicine, 2009,92(4 ): 324-332.