If the property class field is not provided or is empty, {HEAD ~ an object} of {TAIL ~ a default discovery class} is preferably instantiated 
If the property class field is not provided or is empty , { HEAD ~ an object } of { TAIL ~ a default discovery class } is preferably instantiated
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH