Nasruddin, N., E. M. Harahap, C. Hanum, and L. A. M. Siregar. “Response of Three Varieties of Patchouli (Pogostemon Cablin, Benth) Due to Drought Stress”. International Journal of Sciences: Basic and Applied Research (IJSBAR), vol. 30, no. 2, Nov. 2016, pp. 286-94, https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/6470.