def clear(self):
    """Clear the list of cited papers (including any default citations)."""
    self._array[:] = [False]*len(self._array)

def register(self, inspire_key):
    """Register a paper to be cited. The intended use is that this method
    should be called only when the referenced functionality is actually being used.
    Parameters
    ----------
    inspire_key : str
        The INSPIRE texkey for the paper to be cited
    """
    try:
        self._array[self._all_citations[inspire_key]] = True
    except KeyError:
        from flavio.util import get_datapath
        yaml_path = get_datapath('flavio', 'data/citations.yml')
        raise KeyError(
            f'The inspire key must be contained in {yaml_path}. '
            f'The key `{inspire_key}` was not found there.'
        )

def reset(self):
    """Reset the list of cited papers back to only the default ones."""
    self.clear()
    for inspire_key in self._initial_citations:
        self.register(inspire_key)