His English language novels , such as " At Swim - Two - Birds " and " The Third Policeman " , were written under the " pen name " Flann O'Brien .
Head entity: the third policeman Q2483345 17 18 19
Tail entity: at swim-two-birds Q759330 8 9 10 11 12 13
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Inverse relation (tail \u2192 head): P156