Nurestri Abd. Malek, Sri, Halijah Ibrahim, Hong , S.L, Lee , G.S, Chan, K.S, Mashitah Mohd. Yusoff, and Nor Azah Mohd. Ali. 2005. “Essential Oils of Zingiber Ottensii Valet. and Zingiber Zerumbet (L.) Sm. From Sabah, Malaysia”. Malaysian Journal of Science 24 (1):49-58. http://jummec.um.edu.my/index.php/MJS/article/view/8931.