KREBS, R. D., & WALKER, R. D. (1971). Highway materials. McGraw-Hill.
芝加哥风格引文KREBS, Robert D., 与 Richard D. WALKER. Highway Materials. New York: McGraw-Hill, 1971.
MLA引文KREBS, Robert D., 与 Richard D. WALKER. Highway Materials. McGraw-Hill, 1971.
警告：这些引文格式不一定是100％准确.