@article{RSMUP_1967__38__23_0,
     author = {Crapo, Henry H.},
     title = {Geometric duality},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {23--26},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {38},
     year = {1967},
     mrnumber = {220638},
     zbl = {0149.25902},
     language = {en},
     url = {http://www.numdam.org/item/RSMUP_1967__38__23_0/}
}