Belgrade Marathon 2017
Public Enterprise of PTT Srbija
<a rel="nofollow" class="external autonumber" href="http://www.posta.rs/struktura/eng/filatelija/prigodne-postanske-marke/prigodne-postanske-marke-2017.asp">[1]</a> <a rel="nofollow" class="external autonumber" href="http://www.wnsstamps.post/en/stamps/RS028.17">[2]</a>