@article{TAC_2003_11_a17,
     author = {Matias Menni},
     title = {Symmetric monoidal completions
and the exponential principle among labeled combinatorial structures},
     journal = {Theory and applications of categories},
     pages = {397--419},
     publisher = {mathdoc},
     volume = {11},
     year = {2003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2003_11_a17/}
}