One useful way to find additional resources for your research is to look at the sources the author of A People's History of the United States consulted for each chapter. There aren't citations at the end of chapters, but there is a Bibliography at the end of the book.
Once you get to the bibliography, you'll see there is a heading for each chapter, and the cited works are listed alphabetically there:
From here, you can copy the title of the book or article title. For books, the title will be the part in italics. Article or chapter titles will be in quotation marks. After you have the title you're looking for, you can search for it in OneSearch to see if CSUN has the item.
If you don't see what you're looking for, try our tutorials on Finding Books or Finding Articles