Ville Mäkelä, Tuuli Keskinen, John Mäkelä, Pekka Kallioniemi, Jussi Karhu, Kimmo Ronkainen, Alisa Burova, Jaakko Hakulinen, Markku Turunen: What Are Others Looking at? Exploring 360° Videos on HMDs with Visual Cues about Other Viewers. TVX 2019: 13-24