The editor has retracted this chapter [1] because of significant overlap with an earlier published article by Benta and Vaida [2]. Authors Samta Jain Goyal, Arvind K. Upadhyay and Rajeev Goyal agree with this retraction. Author R. S. Jadon has not responded to any correspondence from the publisher about this retraction.

[1] Goyal S. J., Upadhyay A. K., Jadon R. S., Goyal R. (2018) Real-Life Facial Expression Recognition Systems: A Review. In: Satapathy S., Bhateja V., Das S. (eds) Smart Computing and Informatics. Smart Innovation, Systems and Technologies, vol 77. Springer, Singapore https://doi.org/10.1007/978-981-10-5544-7_31.

[2] K.-I. Benta, M.-F. Vaida, “Towards Real-Life Facial Expression Recognition Systems,” Advances in Electrical and Computer Engineering vol. 15, no. 2, pp. 93–102, 2015, https://doi.org/l0.4316/AECE.2015.02012.