@article{NSJOM_2004_34_2a_0,
     author = {S. A. Achache},
     title = {A note about 

 the order of an extensive map},
     journal = {Novi Sad Journal of Mathematics},
     pages = {1-3},
     year = {2004},
     volume = {34},
     number = {2},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_2004_34_2a_0/}
}