@article{10_4064_cm_57_1_137_143,
     author = {H. W. Pu and H. H. Pu},
     title = {Pseudo-symmetric differentiation},
     journal = {Colloquium Mathematicum},
     pages = {137--143},
     publisher = {mathdoc},
     volume = {57},
     number = {1},
     year = {1989},
     doi = {10.4064/cm-57-1-137-143},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-57-1-137-143/}
}