Ultrasonographic parameters of the liver, spleen and kidneys among a cohort of school children in Sri Lanka oleh Dianne Tania Dayanthi Warnakulasuriya, Pattiya Pathirennahalage Uddika Chamila Peries, Yaddehi Arachchillage Chaminda Rathnasekara, KaluArachchige Thushari Madurika Jayawardena, Angappulige Upasena, Anada Rajitha Wickremasinghe