@article{10_1017_S0017089500004067,
     author = {Petrich, Mario},
     title = {The conjugate hull of an inverse semigroup},
     journal = {Glasgow mathematical journal},
     pages = {103--124},
     year = {1980},
     volume = {21},
     number = {1},
     doi = {10.1017/S0017089500004067},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500004067/}
}