Herba, C. M., Landau, S., Russel, T., Ecker, C., & Philips, M. L. (2006). The development of emotion-processing in children: Effects of age, emotion, and intensity. Journal of Child Psychology and Psychiatry, 47(11), 1098-1106. http://doi.org/10.1111/j.1469-7610.2006.01652