Williny, Rina Friska B Siahaan, & Elserra Siemin Ciamas. (2021). Markov Analysis: Strategi Mempertahankan Brand Image Produk Unggulan Sumatera Utara. Jurnal E-Bis, 5(1), 287-295. https://doi.org/10.37339/e-bis.v5i1.774