docs: def children(self, val: list):
          """ Sets children
  
          :param val: List of citation children
          """
          final_value = []
          if val is not None:
              for citation in val:
                  if citation is None:
                      continue
                  elif not isinstance(citation, (BaseCitation, type(self))):
                      raise TypeError("Citation children should be Citation")
                  else:
                      if isinstance(self, BaseCitation):
                          citation.root = self.root
                      else:
                          citation.root = self
                      final_value.append(citation)
  
          self._children = final_value