def false_repr(self, value):
        """Validate and set the logical false representation."""
        if isinstance(value, str):
            if not (value.lower().startswith('f') or
                    value.lower().startswith('.f')):
                raise ValueError("Logical false representation must start "
                                 "with 'F' or '.F'.")
            else:
                self._logical_repr[0] = value
        else:
            raise TypeError('Logical false representation must be a string.')