1. Wohlers Report 2019;Ian,2021
2. Metal AM Market Opportunities and Trends 2021
https://www.3dpbm.com/product/metal-am-market-opportunities-and-trends/
3. Is the Oil & Gas Industry Ready for 3D Printing?
https://amfg.ai/2021/09/06/is-the-oil-gas-industry-ready-for-3d-printing/#language_switcher
4. The Market for Additive Manufacturing in the Oil and Gas Sector
https://www.smartechanalysis.com/reports/the-market-for-additive-manufacturing-in-the-oil-and-gas-sector-2018-2029/
5. 3D printing using concrete extrusion: A roadmap for research