Gaya APA

Wibisono,Widyastuti, ., al, E. (1999). Proceeding of International Conference on occupational health and safety in the informal sector . Jakarta: Ministry of Health and safety of Indonesia.

Gaya MLA

Wibisono,Widyastuti, ., al, Et. "Proceeding of International Conference on occupational health and safety in the informal sector". Jakarta: Ministry of Health and safety of Indonesia, 1999. print.