1. Web site of the Office of the Telecommunications Authority, HKSAR, http://www.ofta.gov.hk/frameset/facts_index_eng.htm.
2. IEEE C95.1:1999, Safety levels with respect to human exposure to radio frequency electromagnetic fields, 3 kHz to 300 GHz, IEEE standard, 1999.
3. EN 50360:2001, Product standard to demonstrate the compliance of mobile phones with the basic restrictions related to human exposure to electromagnetic fields (300 MHz-3 GHz), EN standard, 2001.
4. Current and SAR induced in a human head model by the electromagnetic fields irradiated from a cellular phone