Acknowledgements

This session of the course was written by Anna Page on behalf of the Free Learning team at The Open University.

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Images

Figure 1: Source: How to Attribute Creative Commons Photos, by FOTER, CC BY-SA 3.0

Figure 2: by Bryan Mathers http://bryanmathers.com/ CC BY ND

Figure 3: Stephen Craven CC-BY-SA-2.0 as displayed on http://www.geograph.org.uk/ photo/ 4999640

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