Acknowledgements

This free course was written by Christine Leach, Silvia Bergamini, Calum MacCormick and Andrew Norton and first published in June 2025.

OpenLearn editor: Dale Harry

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:

Images

Course image: bpawesome/istock/Getty Images

Figure 1: Radek Grzybowski/Unsplash

Every effort has been made to contact copyright owners. If any have been inadvertently overlooked, the publishers will be pleased to make the necessary arrangements at the first opportunity.

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