This invention provides an apparatus and process for producing {TAIL ~ heavy crude oil} from {HEAD ~ a subterranean formation} penetrated by a well bore 
This invention provides an apparatus and process for producing { TAIL ~ heavy crude oil } from { HEAD ~ a subterranean formation } penetrated by a well bore
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH