“Analisis Faktor Penyebab Perubahan Kontrak Pada Pekerjaan Pembangunan RS UPT Vertikal Surabaya : Analysis Factors Causing Contract Changes In The Construction Of UPT Vertical Hospital Surabaya RS UPT Vertikal Surabaya” (2025) CONCRETE: Construction and Civil Integration Technology, 3(01), pp. 10–17. doi: 10.25139/concrete.v3i01.9958.