SIAHAAN, Matdio; SINAGA, Jhonni; PANGARIBUAN, David. Comparative Analysis of Optimal Stock Portfolio Results using The Markowitz Method and a Single Index (Study on LQ 45 Company Shares Listed on the Indonesia Stock Exchange Period January – December 2024). Greenation International Journal of Economics and Accounting, [S. l.], v. 4, n. 2, p. 172–180, 2026. DOI: 10.38035/gijea.v4i2.902. Disponível em: https://research.e-greenation.org/GIJEA/article/view/902. Acesso em: 13 jun. 2026.