1. Land transportation system report by Cisco.
http://www.cisco.com/c/dam/global/pt_pt/assets/ciscoconnect-2013/pdf/16_outubro_helder_antunes.pdf
. Accessed 11 Sept 2018
2. Viola, P.M.J.: Rapid object detection using a boosted cascade of simple features. In: IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR), Kauai, USA (2011)
3. Chaudhari, M.S.S.: A review on Face Detection and study of Viola Jones method. Int. J. Comput. Trends Technol. 25, 54–61 (2015)
4. Takuya, K.A.H.: Selection of histograms of oriented gradients features for pedestrian detection. In: Neural Information Processing, Kitakyushu, Japan (2007)
5. Dalal, N.B.T.: Histogram of oriented gradients for human detection. In: Computer Vision and Pattern Recognition, San Diego (2005)