On 16 December 1948 , Poland 's primary two communist parties , the Polish Socialist Party and the Polish Workers ' Party , were combined to form Polish United Workers ' Party .
Head entity: polish united workers' party Q537303 27 28 29 30 31
Tail entity: polish workers' party Q687409 18 19 20 21
Relation (head \u2192 tail): P156
Inverse relation (tail \u2192 head): P155