North Downs (English Wikipedia)

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mvgs.org.uk

Lester, DE (2015). "Geomorphology of the Mole Valley" (PDF). Mole Valley Geological Society. Archived (PDF) from the original on 16 November 2017. Retrieved 17 July 2020.

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naturalengland.org.uk

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"North Downs Natural Area profile" (PDF). English Nature. August 1997. Archived from the original (PDF) on 27 October 2015. Retrieved 12 September 2007.

ruxley-gravel-pits.org.uk

Waite, Anne, ed. (2000). The Kent red data book: A provisional guide to the rare and threatened flora and fauna of Kent (PDF). Kent County Council. p. 131. ISBN 978-1-9015-0947-2. Archived from the original (PDF) on 13 September 2012.

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West G, Dumbleton MJ (1972). "Some observations on swallow holes and mines in the chalk". Quarterly Journal of Engineering Geology. 5 (1–2): 171–177. doi:10.1144/GSL.QJEG.1972.005.01.16. S2CID 129120488.

web.archive.org

"North Downs Natural Area profile" (PDF). English Nature. August 1997. Archived from the original (PDF) on 27 October 2015. Retrieved 12 September 2007.
"d | Origin and history of d by Online Etymology Dictionary". Etymonline.com. Archived from the original on 14 May 2011. Retrieved 16 September 2017.
The Mountains of England of Wales, Botley Hill, http://www.hill-bagging.co.uk/mountaindetails.php?qu=Ma&rf=3686 Archived 3 May 2014 at the Wayback Machine, Retrieved 4 March 2012
Simon Edwardes (2001). "County Tops". The Mountains of England and Wales. Archived from the original on 3 May 2014. Retrieved 20 April 2014.
The Mountains of England and Wales, Westerham Heights, http://www.hill-bagging.co.uk/mountaindetails.php?qu=Ma&rf=5503 Archived 3 May 2014 at the Wayback Machine, Retrieved 4 March 2012
Anon. "Clay-with Flints formation". The BGS Lexicon of Named Rock Units. BGS. Archived from the original on 9 September 2017. Retrieved 3 May 2017.
Lester, DE (2015). "Geomorphology of the Mole Valley" (PDF). Mole Valley Geological Society. Archived (PDF) from the original on 16 November 2017. Retrieved 17 July 2020.
"What's special about chalk grassland?". National Trust. National Trust. Archived from the original on 25 October 2019. Retrieved 25 October 2019.
Waite, Anne, ed. (2000). The Kent red data book: A provisional guide to the rare and threatened flora and fauna of Kent (PDF). Kent County Council. p. 131. ISBN 978-1-9015-0947-2. Archived from the original (PDF) on 13 September 2012.
"Britain's Orchids, Lady Orchid". Wild Guides and English Nature. Archived from the original on 3 March 2016. Retrieved 12 September 2007.
"Prehistory and The Romans". Guildford Borough. Archived from the original on 22 December 2007. Retrieved 21 February 2008.