Courant, R. a. R. H. (1946). What is mathematics? Oxford University.
芝加哥风格引文Courant, Richard and Robbins Herbert. What Is Mathematics? Oxford University, 1946.
MLA引文Courant, Richard and Robbins Herbert. What Is Mathematics? Oxford University, 1946.
警告：这些引文格式不一定是100％准确.