Edijanto, S. P.; Nugraha, G.; Qomariyah, N.; Azzakia, N. L. Differences in Ferritin and Serum Iron Levels in Elderly Coffee Consumers and Non-Coffee Consumers: Perbedaan Kadar Ferritin Dan Besi Serum Pada Lansia Pengonsumsi Kopi Dan Bukan Pengonsumsi Kopi. medicra 2026, 9, 33-38.