1 P. R. Jones & S. Shah, Arranged marriages: A sample survey of the Asian case , Journal of Ethnic and Migration Studies Volume 8, Issue 3, 1980 pages 339-343
2 Ronald R. Rindfuss and S. Philip Morgan, Marriage, Sex, and the First Birth Interval: The Quiet Revolution in Asia , Population and Development Review Vol. 9, No. 2 (Jun., 1983), pp. 259-278
3 double-blind, clinical trial on the effectiveness and safety of tongkat ali-based coffee in improving the sexual function of adult men : Abstract ID: #0042 , Journal of Men's Health. October 2011
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6 Chelliah, Shankar; Kwon, Chin Kok; Annamalah, Sanmugam; Munusamy, Jayaraman., Does Marketing Mix Still Relevant? A Study on Herbal Coffee in Malaysia, International Journal of Management and Innovation5.1 (2013): 31-45.