Overview of various issues of postage stamps and "stamps" issued directly by Arab Sheikhdoms or with or even without their permission and distinguishing their philatelic value. 29. 12. 2023
Article from the "What do we collect?" series devoted to the problems of proper collection value determination, either for collector's personal needs or for the collection sale. 16. 08. 2016
Article from the series "What do we collect?" dedicated to collecting of a new thematic area of philately which are personalized coupons beside postage stamps. 20. 02. 2014
