a check in reply to a check, typical of Queen endings (See the second Nimzo game in the handout On Manoeuvres )
If you cross-check information, you check that it is correct using a different method or source from the one originally used to obtain it. You have to scrupulously check and cross-check everything you hear His version will later be cross-checked against that of the university They want to ensure such claims are justified by cross-checking with other records. to make certain that something is correct by using a different method to check it again