There is a large amount of literature and plenty of websites on Jørn Utzon and his work.

Some of the most important publications are:

Frampton, Kenneth: Jørn Utzon, Transcultural form and the tectonic metaphor, 1995

Weston, Richard: UTZON - Inspiration - Vision - Architecture, 2002

Pardey, John: To huse på Mallorca, Jørn Utzon Logbog, Volume III, Edition Bløndal, 2004 (Danish)

Keiding, Martin and Kim Dirckinck-Holmfeld (ed.): The Utzon Library: Utzon's Own Houses, The Danish Architectural Press, 2004

Møller, Henrik Steen with Vibe Udsen and Per Nagel (photos). Living Architecture, 2004

Asgaard Andersen, Michael: Jørn Utzon, arkitekturens tilblivelse og virke, 2011(Danish) 

There are also a good many websites that offer a general view of the subject: 

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