N. Kosmyna, Q. Wu, C. -Y. Hu, Y. Wang, C. Scheirer and P. Maes, "Assessing Internal and External Attention in AR using Brain Computer Interfaces: A Pilot Study," 2021 IEEE 17th International Conference on Wearable and Implantable Body Sensor Networks (BSN), 2021, pp. 1-6, doi: 10.1109/BSN51625.2021.9507034.