Tinjauan yuridis pemutusan hubungan kerja atas permintaan pekerja buruh akibat keterlambatan pembayaran upah studi kasus Putusan Mahkamah Agung No. 31 PK/Pdt. Sus 2012 = Juridical analysis on the termination of employment by the workers demand due to late payment of wages case study the supreme court decision no. 31 PK/Pdt.Sus 2012