Pengaruh budaya organisasi dan program keselamatan dan kesehatan kerja terhadap produktivitas kerja PT Wijaya Karya (Persero) Tbk: studi pada pegawai Indirect Proyek PLTGU Muara Karang Tbk = The impact of organizational culture and occupational safety and health program on work productivity PT Wijaya Karya Persero Tbk: a study on indirect employee at Muara Karang Combined Cycle Power Plant