What is the version of the following sentence with correct punctuation?

Although many older history reports across the Earth refers to several different and often very profound natural disasters and floods they can hardly be classified as purely incidental cases where the specified times of events are exactly the same
Although many older history reports across the Earth refers to several different and often very profound natural disasters and floods, they can hardly be classified as purely "incidental" cases where the specified times of events are exactly the same.