The paper describes two ongoing projects carried out by the Mathematical Institute of Serbian Academy of Science and Arts, Belgrade and the Faculty of Mathematics, Belgrade. The projects concern building of electronic resources and presentations of electronic editions of mathematical works in Serbia. The first project is related to retro digitization of old books, articles and the other mathematical works and development of the corresponding virtual library. In the second project a database and www-presentations of some Serbian mathematical journals were created. The resources built in the projects are freely accessible through Internet. These projects are included in a recent initiative on the foundation and development of the National Center for Digitization.