You can ask it a follow-up question for sources. However, it's hit-and-miss.

In a few cases, I've seen it give citations to things that clearly never existed.

For example, I asked it for US auto-pedestrian death statistics. It printed out a nicely formatted table.

Then, I asked it for a source. It pointed me to a specific table on a dot.gov page. The table didn't exist and, according to the Wayback Machine, it never did.

I ended up finding the information the old-fashioned way, and numbers that it gave were way off.

I suspect the majority of folks won't be bother to fact check the data it returns. It's going to be a problem.