@article{SF_1992__44_1_135158, author = {S.L. Lipscomb}, title = {Centralizers in symmetric inverse semigroups: {Structure} and order.}, journal = {Semigroup forum}, pages = {347--355}, year = {1992}, volume = {44}, number = {1}, zbl = {0746.20046}, url = {http://geodesic.mathdoc.fr/item/SF_1992__44_1_135158/} }