5GUERRERO M L, MORROW R C, CALVA J J, et al. Rapid ethnographic assessment of breasffeeding practices in periurban Mexico City [J]. Bull World Health Organ, 1999, 77 (4) : 323 -330.
6De ZOYSA I, HABICHT J P, PELTO G, et al. Research steps in the development and evaluation of public health interventions [J]. Bull World Health Organ, 1998, 76 (2) : 127 - 133.
7MARTINES J C, ASHWORTH A, KIRKWOOD B. Breast - feeding among the urban poor in southern Brazil: reasons for termination in the first 6 months of life [J]. Bull World Health Organ, 1989, 67 (2) : 151 - 161.
8DIMOND H J, ASHWORTH A. Infant feeding practices in Kenya, Mexico and Malaysia. The rarity of the exclusively breast - fed infant [J]. Hum Nutr Appl Nutr, 1987, 41 (1) : 51 - 64.
9EARLE S. Factors affecting the initiation of breastfeeding: implications for breastfeeding promotion[J]. Health Promot Int, 2002, 17 (3): 205 -214.