1. Adobe Inc. (2021). Adobe Lightroom Classic. Available at: https://www.adobe.com/products/photoshop-lightroom
2. Adobe Inc. (2022). Adobe Photoshop. Available at: https://www.adobe.com/products/photoshop
3. Burl, A. (1976). The Stone Circles of the British Isles. Yale University Press.
4. Burl, A. (2005). A Guide to the Stone Circles of Britain, Ireland and Brittany, Revised Edition, Yale University Press.