Spontaneous webcam instance for user attention trackingRobal, TarmoPICMET19 : Portland International Conference on management of engineering and technology : Technology and Management in the World of Intelligent Systems : proceedings2019 / 8 p. : ill https://doi.org/10.23919/PICMET.2019.8893798 Webcam-based attention tracking in online learning: a feasibility studyRobal, Tarmo; Zhao, Yue; Lofi, Christoph; Hauff, ClaudiaIUI '18 : Proceedings of the 2018 Conference on Intelligent User Interface, Tokyo, Japan, March 07-11, 20182018 / p. 189-197 : ill https://doi.org/10.1145/3172944.3172987