KAR, Sitanshu Sekhar; RAMALINGAM, Archana. Is 30 The Magic Number? Issues In Sample Size Estimation. National Journal of Community Medicine, [S. l.], v. 4, n. 01, p. 175–179, 2013. Disponível em: https://njcmindia.com/index.php/file/article/view/1489. Acesso em: 26 jul. 2025.