Kalalo, L., Takumansang-Sondakh, D. and Wahani, A. 2013. Cotinine and interferon-gamma levels in pre-school children exposed to household tobacco smoke. Paediatrica Indonesiana. 53, 5 (Oct. 2013), 287-90. DOI:https://doi.org/10.14238/pi53.5.2013.287-90.