Centro Vasco de Arquitectura
Euskal Herriko Arkitektura Ikerkundea
http://www.abebooks.com/9789686085679/JOSEF-HOFFMANN-GRESLERI-Giuliano-968608567X/plp
http://www.abebooks.co.uk/servlet/BookDetailsPL?bi=10833687919&searchurl=tn%3Djosef%2Bhoffmann%26sortby%3D17%26an%3Dgresleri%2Bgiuliano