Columbia subject headings:
Critical theory.
Luhmann, Niklas, 1927-1998.
Phenomenology.
Social systems.
Sociology--Philosophy.
Harvard subject headings:
Critical theory
Luhmann, Niklas, 1927-1998
Phenomenology.
Social systems.
Sociology--Philosophy
Princeton subject headings:
Critical theory.
Luhmann, Niklas, 1927-1998.
Phenomenology.
Social systems.
Sociology--Philosophy.