[http://www.epd.gov.hk/epd/english/environmentinhk/waste/prob_solutions/files/GHK_study.pdf “Assessment of Benefits and Effects of the Plastic Shopping Bag Charging Scheme” by GHK (Hong Kong) Ltd. :
switching to alternative bag types is of paramount importance: in Eire it has been estimated thatthis switching resulted in an increase in bag weight by up to 11 times per bag, an increase in bulkby up to 18 times and a cost multiplier of up to 13 times.] 互联网档案馆的存檔，存档日期2013-11-06.
[http://www.epd.gov.hk/epd/english/environmentinhk/waste/prob_solutions/files/GHK_study.pdf “Assessment of Benefits and Effects of the Plastic Shopping Bag Charging Scheme” by GHK (Hong Kong) Ltd. :
switching to alternative bag types is of paramount importance: in Eire it has been estimated thatthis switching resulted in an increase in bag weight by up to 11 times per bag, an increase in bulkby up to 18 times and a cost multiplier of up to 13 times.] 互联网档案馆的存檔，存档日期2013-11-06.
