Morton, R. L. (1937). Teaching arithmetic in elementary school. Silver Burdett company.
芝加哥风格引文Morton, Robert Lee. Teaching Arithmetic in Elementary School. New York, boston [etc.]: Silver Burdett company, 1937.
MLA引文Morton, Robert Lee. Teaching Arithmetic in Elementary School. Silver Burdett company, 1937.
警告：这些引文格式不一定是100％准确.