@article{ADM_2003_2_a2,
     author = {Ahmet A. Husainov and Hamza \c{C}ali\c{s}ici},
     title = {Flows in graphs and the homology of free categories},
     journal = {Algebra and discrete mathematics},
     pages = {36--46},
     publisher = {mathdoc},
     number = {2},
     year = {2003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ADM_2003_2_a2/}
}