Setya Negara, A.I., Destiana Tunggal Pramesti and Muhammad Sodikun 2023. Green Marketing in Sustainable Business: Utilizing Fly Ash as a Cement Substitute to Reduce CO2 Emissions in the Mortar Industry. Open Access Indonesia Journal of Social Sciences. 7, 2 (Dec. 2023), 1398-1404. DOI:https://doi.org/10.37275/oaijss.v7i2.223.