1. 360iResearch (2021) Underground Utility Mapping Market Research Report, 207p.
2. Ahn, E.Y., Lee, J.W., Bae, J.H. and Kim, J.M. (2020) Analysis of Emerging Geo-technologies and markets focusing on digital twin and environmental monitoring in response to Digital and Green New Deal. Econ. Environ. Geol., v.53(5), p.609-617. doi: 10.9719/EEG.2020.53.5.609
3. Smart Earth: A meta-review and implications for environmental governance
4. BGS Press (2021) BGS collaborates on new £1 million EPSRCfunded digital research project to help make urban growth more sustainable, https://www.bgs.ac.uk/news/bgs-collaborates-on-new-1-million-epsrc-funded-digital-research-project-to-help-makeurban-growth-more-sustainable.
5. Busan Metropolitan City (2014) The deepest urban railway station in the country_Mandeok Station, 66 m. https://www.busan.go.kr/news/specnews/view?bbsNo=6&dataNo=45881&srchThemeNo=131.