@article{SMJ2_2007_33_2-3_a7,
     author = {Al-Mahameed, M. M.},
     title = {Extended {Maximum} {Principles}},
     journal = {Serdica Mathematical Journal},
     pages = {351--362},
     year = {2007},
     volume = {33},
     number = {2-3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SMJ2_2007_33_2-3_a7/}
}