de By, R. A., Norkhair Ibrahim, & Zulkepli Majid. (2002). Prinsip sistem maklumat geografi. Universiti Teknologi Malaysia.
Chicago Style (17th ed.) Citationde By, Rolf A., Norkhair Ibrahim, and Zulkepli Majid. Prinsip Sistem Maklumat Geografi. Skudai: Universiti Teknologi Malaysia, 2002.
MLA (9th ed.) Citationde By, Rolf A., et al. Prinsip Sistem Maklumat Geografi. Universiti Teknologi Malaysia, 2002.
Warning: These citations may not always be 100% accurate.