id	keyword
ejpam-2338	inverse
ejpam-2338	inverse semigroups
ejpam-2338	theorem
ejpam-2338	partial
ejpam-2338	munn
ejpam-2338	mcalister
ejpam-2338	groupoid
ejpam-2338	ehresmann
ejpam-2338	congruence
ejpam-2338	notion