I don't have links to papers but I would have thought that Google would get you enough hits there.

The seal ring is used to isolate the active silicon area from the external environment, basically from humidity. If moisture creeps into your die over time, then it may cause corrosion and change impedances between the various nodes on your chip. This would be a big problem which would likely cause your design to malfunction sooner or later.

I cannot imagine any reason not to use the seal ring. There are some cases where people are trying to make a really small ASIC and cutting down the cost but even then, the seal ring is quite a small thing and it saves you the trouble of having to worry about what might happen if you didn't have it.

By the way, depending on your process and quality flow, you may not even be allowed to do anything like leaving out the seal ring.

Vivek

Seal ring usually gets tied to a lot of  substrate taps
and then ends up getting tied to I/O ring ground.