@article{NSJOM_2005_35_2a_6,
     author = {V. Popa},
     title = {A general fixed point theorem 

 for two pairs 

 of mappings on two metric spaces},
     journal = {Novi Sad Journal of Mathematics},
     pages = {79-83},
     publisher = {mathdoc},
     volume = {35},
     number = {2},
     year = {2005},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_2005_35_2a_6/}
}