Gaya APA

Yan, S. et al (2009). Simultaneous transesterification and esterification of unrefined or waste oils over ZnO-La2O3 catalysts . London: Elsevier B.V..

Gaya MLA

Yan, Shuli. et al. "Simultaneous transesterification and esterification of unrefined or waste oils over ZnO-La2O3 catalysts". London: Elsevier B.V., 2009. e-journal.