Jędrzejczyk, I., and J. Przybytniowski. “TRANSFRONTIER INSURANCE SERVICES AS THE DIRECTION OF THE EUROPEAN COMMON MARKET DEVELOPMENT”. Acta Scientiarum Polonorum. Oeconomia, Vol. 8, no. 4, Dec. 2009, pp. 61-69, https://js.wne.sggw.pl/index.php/aspe/article/view/3854.