Immigration is a type of Migration. Migration is a type of Event. Event is related to Work. Work is etymologically related to Organ. 
Regional is a different concept from Local. Local is a synonym of Citizen. Citizen is related to Voting. Voting is related to Poll. 
Immigration --IsA--> Migration --IsA--> Event <--RelatedTo--> Work --EtymologicallyRelatedTo--> Organ 
Regional <--DistinctFrom--> Local <--Synonym--> Citizen <--RelatedTo--> Voting <--RelatedTo--> Poll 