While doing your research, all of the following would be good secondary sources to use to develop a general overview about the Vietnam War, except:

An interview with a veteran is a firsthand account, so it is a primary source rather than a secondary source. Encyclopedias, history textbooks, and general history websites summarize and interpret information from other sources, making them useful secondary sources for a general overview. Therefore, the exception is an interview with a veteran of the war.

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