… D-semigroups (which need not satisfy any semiadequacy condition) and what we call co-restriction
constellations… ordering on the constellations, since the D-semigroups themselves are …

… the theories of projection algebras and constellations, respectively. … d-semigroups is a
very broad class of semigroups and can be defined by identities. In fact, the class of d-semigroups …

… D-inverse constellations are equivalent … constellations rather than ordered groupoids,
presenting an alternative formulation and proof of the ESN Theorem using D-inverse constellations…

… of a constellation (a kind of “one-sided category”). A left restriction semigroup becomes a
constellation … In [20], generalised D-semigroups were defined in terms of a generalised Green’s …

… of the most important special kinds of D-semigroups, defined by the … Attention then turns to
D-semigroups having an involution … arise from such involuted D-semigroups. Versions of the …

… constellations with a well-behaved range operation are equivalent to ordered categories with
restrictions. As a special case, we show that the constellation … but constellations having a …

… compared to (generalised) D-semigroups. Finally the special … ; this gives the generalised
D-semigroups studied by Stokes [… D-semigroups is identified as the class of D-semigroups with …

… a constellation allows us to obtain some connections with categories, cementing the idea that
a constellation … constellations may be used to capture D-semigroups, including those of [1]. …

Restriction semigroups model algebras of partial maps under composition and domain. Here
we consider restriction semigroups for which the usual Boolean operations on domains are …

… a constellation allows us to obtain some connections with categories, cementing the idea that
a constellation … shows how constellations may be used to capture D-semigroups, including …