From 17-19th October 1958, Delia went with Jonathan Harvey to Expo 58, l'Exposition Internationale et Universelle, in Brussels, where they heard the world première of Varese's "Poème Eléctronique" at its world première, performed on 425 speakers.
- Recreating the Philips Pavilion posted by Joe Drew, January 16, 2010 on the ANABlog Archive.
- Expo 58 on wikipedia.org
- Legend to the Expo 58 group photo.
- Personal communication from Jonathan Harvey's daughter, May 2017.
- Professor Chou Wen-chung, musical executor of the Varese estate, on Edgard Varese's "Poem Electronique" on furious.com
- These Hopeful Machines, at 6:05.