The collaboration of authors on the literature on Lotka’s law published since 1922 to June 2010, was analyzed. 651 documents produced by 728 different authors were identified; 53.3% of those documents were produced by single authors and 46.7% were produced in collaboration by two or more authors. The collaboration index (CI), the degree of collaboration (GC) and the coefficient of collaboration (CC) indexes were used to measure the extent of collaboration. Collaboration begun at the mid-60s and since then is growing in a constant rate. Collaboration was ratified by the three indexes studied
