1[4]Porter and Judson,the Iocation of us currency:how much is abroad,Board of Governors of the Federal Reserve System,1996
2[5]Hawkins,the demand for hong kong dollars,HKMA Quarterly Bulletin,1997
3[6]Chan,Currency substitution between the hong kong dollar and renminbi in south china,hong kong institute for monetary research,2001
4[7]Wensheng Peng and Joanna Y L Shi,Offshore use of currency:Hong Kong's experience,BIS,2002
5[10]Greenwood (1990):"An estimate of the Hong Kong dollar currency circulation in guangdong Province",Asian Monetary Monitor,July-August 1990,pp 37-44