T. Medaiskis, T. Gudaitis, and J. Mečkovski, “THE EFFECT OF SECOND PILLAR PENSION TO OLD AGE PENSION: LITHUANIAN CASE”, Int. J. Econ. Sci., vol. 5, no. 4, pp. 20–31, Dec. 2016, doi: 10.20472/ES.2016.5.4.002.