Chilean School of Biology of Cognition: Offering overview of Maturana's contributions to psychology, 'Ask Professor Maturana', and online archive editions of important articles.
Cybernetics & Human Knowing: A Journal of Second Order Cybernetics, Autopoiesis and Cyber-Semiotics.
Luis E. Bastias: Contributions to the development of Valparaiso's Autopoiesis Theory
Radical Constructivism: The most comprehensive Webspace on constructivist epistemology (a component of the second-order cybernetics worldview), especially the work of von Glasersfeld and von Foerster
Towards an Ecology of Mind: Well-organized site addressing (e.g.) Gregory Bateson, Humberto Maturana, Ernst von Glasersfeld, Heinz von Foerster, and George Kelly.