lmplikasi perpecahan Partai Rakyat Demokratik (PRD) terhadap radikalisasi kelompok kiri di Indonesia (Studi Kasus Partai Rakyat Demokratik) = implications disunity the Peoples Democratic Party (PRD) against the radicalization of the left group on Indonesia (case study of the peoples democratic party) - Arif Widiyarto, author (Universitas Indonesia, 2011)