An InstanceSpecification can act as a DeploymentTarget in a Deployment relationship, in the case that it represents an instance of a Node. It can also act as a DeployedArtifact, if it represents an instance of an Artifact. Source Unified Modeling Language 2.5.1
Webel Parsing Analysis: A custom Document stereotype (keyword «document») extends the UML standard profile Document that extends Artifact (which is NOT in the UML4SysML intersection). Such a Document may act as the 'source' of a «snippet».
The UML Artifact and its UML standard profile extensions such as «document» Document and «file» File are NOT included in UML4SysML.
SysMLv1.x: Extending the ElementGroup for the Webel Parsing Analysis recipe (a quick look) This content has been marked as discussing an ADVANCED topic! Gallery Tutorial TRAIL: Webel's ultimate guide to Systems Modeling Language (v1) with MagicDraw/Cameo Section 18:01: Logical grouping with the ElementGroup extension of Comment in SysMLv1.x Slide kind UML Profile Diagram
Dr Darren of Webel has always opposed the exclusion of the obviously useful UML Artifact from SysML (but in MagicDraw and Cameo you can sneak it in anyway). After all, systems engineers do use documents quite a bit.