Llewellyn, C., and L. Cram. “Distinguishing the Wood from the Trees: Contrasting Collection Methods to Understand Bias in a Longitudinal Brexit Twitter Dataset”. Proceedings of the International AAAI Conference on Web and Social Media, vol. 11, no. 1, May 2017, pp. 596-9, doi:10.1609/icwsm.v11i1.14924.