1. Ng, P.C., De Silva, L.C.: Head gestures recognition. In: Proceedings of the 2001 International Conference on Image Processing, vol. 3, pp. 266–269. IEEE, Thessaloniki (2001)
2. Fujie, S., Ejiri, Y., Nakajima, K., Matsusaka, Y., Kobayashi, T.: A conversation robot using head gesture recognition as para-linguistic information. In: Proceedings of the RO-MAN 2004. 13th IEEE International Workshop on Robot and Human Interactive Communication, pp. 159–164. IEEE, Kurashiki (2004)
3. Solea, R., Margarit, A., Cernega, D., Serbencu, A.: Head movement control of powered wheelchair. In: Proceedings of the 2019 23rd International Conference on System Theory, Control and Computing, pp. 632–637. IEEE, Sinaia (2019)
4. Suni, S.S., Gopakumar, K.: A real time decision support system using head nod and shake. In: Proceedings of the 2016 International Conference on Circuit, Power and Computing Technologies, pp. 1–5. IEEE, Nagercoil (2016)
5. Lu, P., Zhang, M., Zhu, X., Wang, Y.: Head nod and shake recognition based on multi-view model and hidden Markov model. In: Proceedings of International Conference on Computer Graphics, Imaging and Visualization, pp. 61–64. IEEE, Beijing (2005)