Your second book can be any nonfiction book about a person dealing with the city of Boston. (For these purposes, it’s OK if they come from a surrounding time like Cambridge, Concord, Salem, or Foxborough; please stick to Massachusetts, though). You must have not previously read it; it must have originally been printed as a book. One good place to find e-texts to download is archive.org (and its sister site, openlibrary.org; you can plug in search terms there and find text files to download. You may need to read a little bit of a bio somewhere to ensure that your figure is connected to Boston. Project Gutenberg is also good.