The article deals with analysis of model data formats suitable for metadata description of digital objects (artifacts) occurring in scientific social network applications. The emphasis of analyzes is on the issue of a metadata description of artefact links to other artifacts and artifact links to individuals. The examined metadata formats include LOM (Learning Objects Metadata), MODS (Metadata Object Description Schema) and DC (Dublin Core). The article also deals with dictionaries of controlled descriptors used to refine and unify the metadata description for agricultural research.