@article{10_4064_cm_26_1_49_54,
     author = {Homer V. Craig},
     title = {On the extensor structure of a formulation given by {W.} {\'Slebodzi\'nski}},
     journal = {Colloquium Mathematicum},
     pages = {49--54},
     publisher = {mathdoc},
     volume = {26},
     number = {1},
     year = {1972},
     doi = {10.4064/cm-26-1-49-54},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-26-1-49-54/}
}