@article{NSJOM_1987_17_1a_16,
     author = {Petrovi\'c Vojislav},
     title = {On unavoidable subdigraphs of 

 tournaments},
     journal = {Novi Sad Journal of Mathematics},
     pages = {229-238},
     publisher = {mathdoc},
     volume = {17},
     number = {1},
     year = {1987},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_1987_17_1a_16/}
}