Difallah, D. et al. 2014. Scaling-Up the Crowd: Micro-Task Pricing Schemes for Worker Retention and Latency Improvement. Proceedings of the AAAI Conference on Human Computation and Crowdsourcing. 2, 1 (Sep. 2014), 50–58. DOI:https://doi.org/10.1609/hcomp.v2i1.13154.