TY - BOOK A1 - Petrovic, Gajo T1 - Marx in the mid-twentieth century, New York (Anchor Books) 1967. Y1 - 1967 ER - TY - BOOK A1 - Petrovic, Gajo T1 - Revolutionäre Praxis, Freiburg (Verlag Rombach) 1969. Y1 - 1969 N1 - With inscription ER -