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Figure 1 top and bottom left: Rose Barton; bottom right: Vaughan Melzer
Figure 2 Vaughan Melzer
This extract is taken from K202 produced by the BBC on behalf of the Open University © 2000 The Open University
Kristen Laprise: http://www.flickr.com/ photos/ kris10lprs/ 3056021115/ [Details correct as of 15 December 2008]
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