Prevalensi peningkatan kadar timah hitam darah dan urin serta koproporfirin urin pada petugas gerbang tol laki-laki di Jakarta serta pengaruh masa kerja = The prevalences of increased blood and urine lead and urine coproporphyrine concentrations in male toll gate employees in Jakarta and the influence of length of employement - Sjarif Hidajat, author (Universitas Indonesia, 1997)