The '''NIST Identifier Collaboration Service''' or '''NICS''', was a general-purpose registry for identifiers, implemented in Tcl, and designed in part to be used to manage resources such as [namespace%|%namespaces] within Tcl. ** Documentation ** [http://www.mel.nist.gov/msidlibrary/doc/usenix.htm%|%Managing Tcl's Namespaces Collaboratively], [Don Libes], 1996: