Hubungan kebisingan terhadap penurunan fungsi pendengaran pada pekerja pabrik kelapa sawit 1 PKS 1 PT X tahun 2014 = The correlation of noise and hearing loss among workers at palm oil mill 1 pom 1 of PT X in the year of 2014 / Edifar Yunus - Edifar Yunus, author (2014)