Introduction and implementation of an immunization information system in the Indonesian province of Daerah Istimewa Yogyakarta: lessons for scaling-up oleh Sulistyawati Sulistyawati, Trisno Agung Wibowo, Rokhmayanti Rokhmayanti, Andri Setyo Dwi Nugroho, Tri Wahyuni Sukesi, Siti Kurnia Widi Hastuti, Surahma Asti Mulasari, Marta Feletto