The effect of several versions of one and the same manuscript published by a journal on its journal impact factor

In the discussion paper on this issue, Vanclay (2011) describes and uncovers several weaknesses of the JIF based on a thorough literature review and detailed empirical analyses. In this short comment we would like to add the results of two studies to the discussion around the JIF. In these studies we investigated the effect of several versions of one and the same manuscript published by a journal on its JIF.