Lessons Learned from Two Usability Studies of Digital Skiing Game with Elderly People in Finland and Japan. - Aung Pyae; Tapani N. Joelsson; Teppo Saarenpää; Mika Luimula; Christina Kattimeri; Paula Pitkäkangas; Patric Granholm; Jouni Smed (Int. J. Serious Games, 2017)