:I added "(self-identification)", because the libertarianism label seemed not to be supported by any third-party source and therefore seemed to be nothing but the party's self-identification. In other party's infoboxes, there is only the ideology as given in neutral, third-party sources and not the self-identification, therefore the tag "(self-identification)" soes not appear. Wikipedia is written from a neutral point of view (NPOV), it is one of three core content policies. Therefore the reader may assume that every statement in Wikipedia, that is not explicitly marked as a particular party or actor's opinion, is a neutral fact. Of course, ideology classifications are never facts, but still the reader may assume that the ideology is classified by neutral analysts by reference to neutral criteria. If we present a particular party's or actor's opinion (i.e. the self-positionment of the party), we have to mark it is such, because otherwise we create the impression that it is a neutral, non-partisan (or third-party) statement. I'd rather not put the self-identification of any party in the respective infobox at all, but only hold onto statements in third-party sources.