For the theoretical background to the VSM and for an account of Beer's work
in Chile, refer to:
Brain of the Firm 2/e Stafford Beer
(John Wiley, 1981) A largely neurocybernetic
development of the VSM and (introduced in the 2nd edition) an account
of Beer's work in Chile.
The VSM is further developed, from a different perspective and with
refinement/standardization of the terminology and diagrammatic conventions,
in:
The Heart of Enterprise Stafford Beer
(John Wiley, 1979) A companion volume to "Brain of
the Firm" which develops the VSM from logical and set-theoretical
principles.
Further useful and illuminating material can be found in the following:
Platform for Change Stafford Beer (John
Wiley, 1975) A book which, while not explicitly
mentioning the Viable System Model, deals with many issues fundamental
to the continuing viability of human systems.
Designing Freedom Stafford Beer (John
Wiley, 1974) A series of six lectures, originally
broadcast on Canadian radio, briefly covering some of the same ground
as "Platform for Change".
Decision and Control Stafford Beer (John
Wiley, 1966) A cybernetic treatment of Operations
Research.
An Introduction to
Cybernetics W. Ross Ashby (Chapman and Hall, 1956)
A thorough and accessible introduction to many aspects
of the theoretical foundations upon which the VSM was built. In
particular this book introduces, develops and justifies the Law of Requisite Variety. It is now
available in PDF format from the link above.
Design for a Brain 2/e W. Ross Ashby
(Chapman and Hall, 1960) This book illustrates a
number of very important concepts, including homeostasis and
ultrastability.