This is another website that talks a little bit more about the Newspaper Preservation Act and its purpose. It also talks about how it promotes competition and keeps failing newspapers alive.
This website talks about the Newspaper Prevention Act of 1970. It defines what the act entails and goes a little in depth as to how it works. Also indirectly talks about the joining of newspapers/ Joint Operating Agreement.
One of the saddest casualties of the digital age is the physical newspaper. For me, one of the saddest parts of that larger loss is the likely end of the age of comic strips.