unwritten

Human rights groups believe there is an unwritten agreement between the four neighbouring countries to allow each other's security forces to pursue dissidents over the border.

That unwritten contract expired in March when the widowed Rufina Cortes died at 97.

Part of the historic legal case hinged on the interpretation of an "unwritten duty of care" that exists under Dutch law, which requires companies to prevent hazardous negligence.

“These things are the unwritten statistics that made Fernando the person, the human being, the man that he was.”

The unwritten rule to only bet foreign horses in Breeders’ Cup turf races was three for three, with all the winners coming from Ireland.