@article{TAC_2004_12_a12,
     author = {Steven Vickers},
     title = {The double powerlocale and exponentiation: {A} case study in geometric logic},
     journal = {Theory and applications of categories},
     pages = {372--422},
     year = {2004},
     volume = {12},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2004_12_a12/}
}