Wijanarko, A., D. A. Y. Sendjaya, M. Gozan, R. W. Soemantojo, A. B. Witarto, K. Asami, and K. Ohtaguchi. “Enhanced Chlorella Vulgaris Buitenzorg Growth by Photon Flux Density Alteration in Serial Bubble Column Photobioreactors”. ASEAN Journal of Chemical Engineering, Vol. 7, no. 2, Dec. 2007, pp. 89-101, https://journal.ugm.ac.id/v3/AJChE/article/view/7679.