Stadtler AC, Gorski PA, Brazelton TB. Toilet training methods, clinical interventions, and recommendations. American Academy of Pediatrics. Pediatrics 1999; 103:1359.
American Academy of Pediatrics Committee on Nutrition. Feeding the child. In: Pediatric Nutrition, 7th ed, Kleinman RE, Greer FR (Eds), American Academy of Pediatrics, Elk Grove Village, IL 2014. p.143.