That seems to be a euro-centric Wiki entry. Suffice to say that your Pontiac uses the 5 x 4.75" wheel bolt circle that's probably THE most common one for aftermarket wheels. I will guarantee, however, that if you DON'T verify the bolt pattern before buying wheels, you'll get the wrong one.
Also, your RWD car wants wheels with as close to zero offset as possible. That means you cannot use the FWD wheels that have a large positive offset. Offset is the measurement of how far the wheel mounting surface is "offset" from the centerline of the rim. Zero offset means that they are lined up. Positive offset means that the rim (and tire) centerline is further inboard than the wheel mounting surface, negative offset means that it is outboard. Unfortunately, most wheel vendors specify backspacing instead of offset, and that's not really useful without also knowing the wheel width and the additional flange thickness on the edges of the rim.