anchor.diff:      WriteResult = rpc:call(FirstNode, antidote, clocksi_execute_tx,
           [[{update, {Key, crdt_pncounter, {increment, a}}}]]),
       ?assertMatch({ok, _}, WriteResult),
  -    increment_counter(FirstNode, Key, N - 1).+    increment_counter(FirstNode, Key, N - 1).
  +
  +%% Auxiliary mehtod that adds numbers in the range
  +%% (Start, Start + N] to an orset.
  +add_elements_starting_from(_FirstNode, _key, 0, _start) ->
  +    ok;
  +add_elements_starting_from(FirstNode, Key, N, Start) ->
  +    WriteResult = rpc:call(FirstNode, antidote, clocksi_execute_tx,
  +        [[{update, {Key, crdt_orset, {{add, Start + N}, ucl}}}]]),
  +    ?assertMatch({ok, _}, WriteResult),
  +    add_elements_starting_from(FirstNode, Key, N - 1, Start).
positive.code:     ?assertEqual(20, ReadResult2),
      lager:info("read_pncounter_old_value_not_in_ets_test OK").
  
  %% Auxiliary method to increment a counter N times.
  increment_counter(_FirstNode, _Key, 0) ->
      ok;
  
negative.code:     lager:info("Vnodes are started up"),
  
      lager:info("Nodes: ~p", [Nodes]),
      read_pncounter_initial_value_not_in_ets_test(Nodes),
      read_pncounter_old_value_not_in_ets_test(Nodes),
      read_orset_old_value_not_in_ets_test(Nodes),
      pass.
  
  %% First we remember the initial time of the counter (with value 0).
  