و آر ایل:https://images.adsttc.com/media/images/5568/d16c/e58e/ce37/8c00/0029/medium_jpg/54ff61e5e58ece05b4000179_2015-pritzker-prize-winner-frei-otto-s-work-in-10-images_frei-otto-institute-for-lightweight-structures-interior.jpg?1432932712
و آر ایل:http://www.archdaily.com/511689/happy-birthday-frei-otto
