National Library (Singapore). Young People's Service. (1993). Window to the sky. Young People's Service, National Library, Singapore, Macmillan/McGraw-Hill.
芝加哥风格引文National Library (Singapore). Young People's Service. Window to the Sky. Singapore : New York: Young People's Service, National Library, Singapore, Macmillan/McGraw-Hill, 1993.
MLA引文National Library (Singapore). Young People's Service. Window to the Sky. Young People's Service, National Library, Singapore, Macmillan/McGraw-Hill, 1993.
警告：这些引文格式不一定是100％准确.