Acknowledgements
This course was written by Professor Tim Benton
Presenter: Tim Benton. Producer: Nick Levinson. Production Assistants: Tricia Cann and Judy Collins.
Except for third party materials and otherwise stated (see terms and conditions [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] ), this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence
Course image: Peggy2012CREATIVELENZ in Flickr made available under Creative Commons Attribution 2.0 Licence.
These extracts have been taken from A216 produced by the BBC on behalf of the Open University © 1999 The Open University.
All other written material contained within this course originated at the Open University
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