Please answer a question about the following article about Boston:

Boston is the largest broadcasting market in New England, with the radio market being the 11th largest in the United States. Several major AM stations include talk radio WRKO, sports/talk station WEEI, and CBS Radio WBZ. WBZ (AM) broadcasts a news radio format. A variety of commercial FM radio formats serve the area, as do NPR stations WBUR and WGBH. College and university radio stations include WERS (Emerson), WHRB (Harvard), WUMB (UMass Boston), WMBR (MIT), WZBC (Boston College), WMFO (Tufts University), WBRS (Brandeis University), WTBU (Boston University, campus and web only), WRBB (Northeastern University) and WMLN-FM (Curry College).

WBUR and WGBH are exaples of what type of radio station?
NPR