I am no expert on this, but Wikipedia cites four sources for the claim that "further examination of the Perot vote in the Election Night exit polls ... showed that Perot siphoned votes nearly equally among Bush and Clinton" (https://en.wikipedia.org/wiki/Ross_Perot_presidential_campai...). FiveThirtyEight put together a little doc making the same claim: http://fivethirtyeight.com/features/the-ross-perot-myth/