In astronomical databases, such as SIMBAD, the number of bibliographical references attached to one astronomical object is continuously growing with the accumulation of published literature over the years. Some objects are cited in many papers, and it may be difficult to identify the most relevant papers, i.e. those which contain extensive results about that object. A first aid for the evaluation of the relevance of a paper consists in reporting additional information about the importance of the object in the article. The number of citations of the object in the paper gives one measure. The relevance can also be evaluated from the location of the citations of the object name in the paper. As an example, when the object name appears in the title of the paper or/and as an "Individual" keyword, that object is generally extensively studied. The variable nomenclature used to designate the astronomical objects is one of the obstacles to be taken into account to derive a significant measure of the impact of the various papers dealing with one object. An evaluation of the classification criteria will be presented.