Robertson, D. (1972). Internationa trade policy (1st.). Sultan Chand & Co.
芝加哥风格引文Robertson, David. Internationa Trade Policy. 1st. Delhi: Sultan Chand & Co, 1972.
MLA引文Robertson, David. Internationa Trade Policy. 1st. Sultan Chand & Co, 1972.
警告：这些引文格式不一定是100％准确.