Qi Han, Dennis Thom, Markus John, Steffen Koch, Florian Heimerl, and Thomas Ertl. TrueLens: Quality Guidance for Document Exploration. IEEE Transactions on Visualization and Computer Graphics, 2019. [PUMA: 2019 vis(us) vis-gis visus:ertl visus:hanqi visus:heimerfn visus:johnms visus:kochsn visus:thomds]