1. WHO, “Global status report on road safety 2015”. Switzerland, World Health Organization”. https://www.afro.who.int/publications/global-status-report-road-safety-2015.
2. Liu B.C., Ivers R., Norton R., Boufous S., Blows S., Lo S. K., “Helmets for preventing injury in motorcycle riders”. Cochrane Database of Systematic Reviews, 2008 Jan 23(1):CD004333.
3. WHO, “Helmets: A Road Safety Manual for Decision-makers and Practictioners”. Geneva, World Health Organization. https://www.who.int/publications/i/item/helmets-a-road-safety-manual-for-decision-makers-and-practitioners.
4. WHO, “Global Status Report on Road Safety 2018”. Geneva, 2018. World Health Organization. http://apps.who.int/bookorders.
5. BPS, “Traffic Accident, Killed Person, Seriously Injured, Slight Injured and Expected of Material Losses Value 2017-2019”. Jakarta, 2022. BPS - Statistics Indonesia. https://www.bps.go.id/indicator/17/513/1/jumlah-kecelakaan-korban-mati-luka-berat-luka-ringan-dan-kerugian-materi.html.