@article{TAC_2013_28_a21,
     author = {Simon Willerton},
     title = {Tight spans, {Isbell} completions and semi-tropical modules},
     journal = {Theory and applications of categories},
     pages = {696--732},
     year = {2013},
     volume = {28},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2013_28_a21/}
}