Transcribing and annotating speech corpora for speech recognition: A three-step crowdsourcing approach with quality control - Hämäläinen, A.; Moreira, F. P.; Avelar, J.; Braga, D.; Dias, M. S. (Proceedings of the 1st AAAI Conference on Human Computation and Crowdsourcing, HCOMP 2013, 2013)