Keywords: Social graph by Đorđe Andrejević-Kun 1978 Yugoslavia stamp.jpg Đorđe Andrejević-Kun http //www catawiki com/catalog/stamps/countries-regions-territories/yugoslavia/1043663-social-graph area ba214557ab776deebec9af0c9684cc5b28d2347f 1978 author Commons Stamps/Public domain templates PD-Yugoslavia + stamps in Serbia-Montenegro are in the public domain See commons Template PD-SCGGov + stamps in Serbia are in the public domain See commons PD-SerbiaGov Stamps of Yugoslavia 1978 Đorđe Andrejević-Kun |