There was a discrepancy: the flight manifest indicated 138 passengers plus two infants, but the cabin contained 139 plus two.
Times, Sunday Times
The bogus bookings would be removed before the flight manifest was printed.
Globe and Mail
It appears as such on the air flight manifest reference.
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By checking flight manifests and comparing them with other information, like watch lists, customs officials were able to find the names of all 19 hijackers quickly.
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