Acknowledgements
This free course was written by Alun Morgan. It was first published in April 2020.
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 4.0 Licence.
The material acknowledged below is Proprietary and used under licence (not subject to Creative Commons Licence). Grateful acknowledgement is made to the following sources for permission to reproduce material in this free course:
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Figure 2: © SilviaJansen/Getty Images
Figure 3: © The Open University
Figure 4: © Thomas Barwick/Getty Images
Figure 5: © nemke/Getty Images
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