using multiple cameras in a scene

I don't know any articles, but it is a pretty common effect in games for like security cameras and such.
What you do is that you render the extra cameras to textures(FBO works best), then you can use those textures in the final scene(with the main camera) in any way you like.
You can get a small FBO tut from my site (link is in my signature below).

just build a camera class which has a function to generate look at matrix from its properties,or uses gluLookAt().. if multible of cameras will not be active at a time(just like security cam screens, or any viewports), you dont need any FBO or render to texture. just update the camera that you are using at that moment.