GRAVA, S. (2002). Urban transportation systems: Choices for communities. McGraw-Hill.
芝加哥风格引文GRAVA, Sigurd. Urban Transportation Systems: Choices for Communities. New York: McGraw-Hill, 2002.
MLA引文GRAVA, Sigurd. Urban Transportation Systems: Choices for Communities. McGraw-Hill, 2002.
警告：这些引文格式不一定是100％准确.