Gaya APA

Piliang, G, W., Rahardja, L. (1990). Proceeding symposium environmetal education approaches in environmental science research and studies . Bogor: Life sciences inter university center faculty of graduate studies bogor agricultural university.

Gaya MLA

Piliang, G., Wiranda., Rahardja, Lukman. "Proceeding symposium environmetal education approaches in environmental science research and studies". Bogor: Life sciences inter university center faculty of graduate studies bogor agricultural university, 1990. Text.