The computer program product 18, wherein {HEAD ~ the persistent federated folder} contains {TAIL ~ members} from an entity of the persistent federated folder 
contains
The computer program product 18 , wherein { HEAD ~ the persistent federated folder } contains { TAIL ~ members } from an entity of the persistent federated folder
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH