"The working class' invincible strength is due to its vanguard party which leads the revolution according to a judicious line. the Marxist line, and sets up a firm worker-peasant alliance to serve as the basis for uniting all popular forces with a view to isolating the enemy to the utmost and overthrowing him."
January 1, 1970
https://en.wikiquote.org/wiki/Tr%C6%B0%E1%BB%9Dng_Chinh