DERMA WATTY SIHOMBING; WIDIANTI LESTARI; NURINDAH DWIYANI; ROSNA YUHERLINA SIAHAAN; RONALD SIMANJUNTAK. E-Portfolio Systems for Seafarer Competency Documentation: Blockchain-Enabled Digital Credentialing and Career Development Tracking. IJISIT: International Journal of Computer Science and Information Technology, [S. l.], v. 2, n. 2, p. 119–132, 2025. DOI: 10.55123/ijisit.v2i2.51. Disponível em: https://ojs.literasisains.id/index.php/ijisit/article/view/51. Acesso em: 28 mar. 2026.