1. Oil and Gas Special Task Force, Enhancing Investment towards 1 Million BOPD Production, Annual Report, 2019, https://www.skkmigas.go.id/assets/ar-skk-migas-2019-indo-rev-170702020.pdf?cf_chl_jschl_tk=pmd_tMZAtljod2_YO_dTGPE3hky33z8GUEmz.9DRmg1wHjE-1630846348-0-gqNtZGzNAhCjcnBsz.
2. Salager, J.L., Surfactants Types and Uses. Version 2. FIRP Booklet # E300-A:Teaching Aid in Surfactant Science & Engineering in English. Universidad De Los Andes, Mérida-Venezuela, 2002
3. Ethan, What’s are Anionic and Nonionic Surfactants?, Safe Household Cleaning, 2018, https://www.safe householdcleaning.com/anionic-nonionic-surfactants/.
4. Tulasi Prasad Niraula, Ajaya Bhattarai, Sujit K Shah, Sujeet Chatterjee, Anionic Surfactants and their uses in different fields, Tribhuvan University, 2012, https://www.researchgate.net/publication/262566119.
5. Surfactants