Obee B. Bob. (2005). Upstream. Upper-Intermediate: Workbook: class cas. 2. Newbury, Express Publishing, 2005.
芝加哥风格引文Obee B. Bob. Upstream. Upper-Intermediate: Workbook: Class Cas. 2. Newbury, Express Publishing, 2005, 2005.
MLA引文Obee B. Bob. Upstream. Upper-Intermediate: Workbook: Class Cas. 2. Newbury, Express Publishing, 2005, 2005.
警告：这些引文格式不一定是100％准确.