1. Margolis, HS. Testimony of Harold S. Margolis May 18, 1999. http://www.cdc.gov/ncidod/disease/hepatitis/marg olis.htm. (18 Nov. 1999).
2. Advisory Committee on Immunization Practices (ACIP). Prevention of hepatitis A through active or passive immunization: Recommendations of the ACIP. 1999; 1-37.
3. Kementerian Kesihatan Malaysia. Kawalan Penyakit Kesihatan. 2000; 37-38.
4. Malaysian Liver Foundation. Useful information: hepatitis B. 1999. http://www.liver.org.my/ (18 Nov. 1999).
5. Galasso GJ, Whitley RJ, Merigan TC. Antiviral agents and human viral diseases. 4th ed. U.S.: Lippincott-Raven; 1997.