Towards a System of Systems Concept
Ackoff, R.L. 1971. "Towards a System of Systems Concepts." Management Science. 17(11), USA.
This source is considered a primary reference for the Concepts of Systems Thinking article.
General systems theory (GST) attempts to create a scientific theory of systems, independent of domain or application technology. There are a wide range of concepts associated with systems under this general movement.
However, while many researchers have done work associated with GST, ir has never really created a coherent set of principles and concepts. This Ackoff paper attempts to tackle this issue by creating a System of System Concepts, to bring together the disperate GST idea. While it is a little old and does not cover more recent ideas of systems of systems (SoS) or chaotic systems, it is still a definitive source for the basic set of concepts.