@article{ref1,
title="The universal semigroup of relations",
journal="Social networks",
year="1979",
author="Boyd, John Paul",
volume="2",
number="2",
pages="91-117",
abstract="Semigroup theory is shown to be a very flexible and appropriate language for the study of social relations. Some of the difficulties with the application of the Lorrain and White (1971) approach to social relations are discussed. It is pointed out that the [`]universal' semigroup of relations is often more suitable for studying relations than the more commonly used [`]semigroup of relations'. Several standard examples and techniques are presented for the study of semigroups. The concept of structural equivalence is generalized to structural similarity modulo a congruence relation. A Galois connection, between the set of relations on the social relations themselves and the lattice of congruences on the universal semigroup, is applied to the evolution of kinship systems.<p />",
language="",
issn="0378-8733",
doi="10.1016/0378-8733(79)90001-7",
url="http://dx.doi.org/10.1016/0378-8733(79)90001-7"
}