1. Public Health Study Programme, Faculty of Health Science, Ngudi Waluyo University, Semarang, Indonesia
2. Department of Environmental Health, Faculty of Public Health, Diponegoro University, Semarang, Indonesia
3. Department of Pediatric, Faculty of Medicine, Diponegoro University/Dr. Kariadi Hospital, Semarang, Indonesia
4. Department of Obstetrics and Gynecology, Faculty of Medicine, Diponegoro University, Semarang, Indonesia