De Cock, L., P. Viaene, N. Van de Weghe, R. Michels, K. Ooms, N. Vanhaeren, A. De Wulf, and P. De Maeyer. “Comparing Written and Photo-Based Indoor Wayfinding Instructions through Eye Fixation Measures and User Ratings As Mental Effort Assessments”. Journal of Eye Movement Research, Vol. 12, no. 1, Jan. 2019, doi:10.16910/jemr.12.1.1.