@article{TAC_2012_26_a18,
     author = {Richard Steiner},
     title = {Opetopes and chain complexes},
     journal = {Theory and applications of categories},
     pages = {501--519},
     publisher = {mathdoc},
     volume = {26},
     year = {2012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAC_2012_26_a18/}
}