Al Kautsar, Rachmad, 		Utaminingrum, Fitri, AND 		Budi, Agung.
" Helmet Monitoring System using Hough Circle and HOG based on KNN" <em>Lontar Komputer : Jurnal Ilmiah Teknologi Informasi</em> [Online], Volume 12 Number 1 (29 March 2021)