Centro Vasco de Arquitectura
Euskal Herriko Arkitektura Ikerkundea
https://buildingfailures.wordpress.com/1973/04/14/1973-john-hancock-tower-boston-massachusetts/
http://johnhancocktower.blogspot.com/2015/02/floor-plans.html
https://www.pcf-p.com/projects/john-hancock-tower/
https://www.nytimes.com/2020/03/04/arts/henry-cobb-dead.html