Gaya APA

Hastoro, I., Riyadi, S. (1998). Towards A Drug Free Singapore Strtegies,Policies And Programmes Against Drugs . Palu: CV Diva Pustaka.

Gaya MLA

Hastoro, Indriyadi., Riyadi, Slamet. "Towards A Drug Free Singapore Strtegies,Policies And Programmes Against Drugs". Palu: CV Diva Pustaka, 1998. Text.