S. P. Appukuttan, S. Balan, G. Natrajan, B. V. Pillai, C. Jayakumar, and R. Bhaskaran, “Symptom Severity, Disability, and Parental Emotional Availability in Children with Functional Somatic Symptoms: A Cross-Sectional Study in Kerala, India”, Natl J Community Med, vol. 16, no. 12, pp. 1243–1253, Dec. 2025.