1. Website
2. https://www.copper.org/resources/properties/microstructure/
3. https://oxford.universitypressscholarship.com/view/10.1093/oso/9780198804079.001.0001/oso-9780198804079-chapter-10
4. https://www.sciencedaily.com/releases/2020/04/200403104003.htm
5. https://www.intechopen.com/books/high-performance-concrete-technology-and-applications/microstructure-of-concrete