SUKESI, Heny. KAJIAN LAYANAN PURNA JUAL. Buletin Ilmiah Litbang Perdagangan, [S. l.], v. 3, n. 2, p. 221–243, 2009. Disponível em: https://jurnal.kemendag.go.id/index.php/bilp/article/view/180. Acesso em: 10 may. 2025.