The # column is the rank of each listed entry for Michał Bejger — rank 1 means this entry is where Michał Bejger has the most articles or citations. A pos and C pos show the reciprocal: the position of Michał Bejger within that entry's own ranked list, by articles and citations respectively. A low value means Michał Bejger is among the most prominent contributors for that entry.
