@article{10_4064_ap102_1_5,
     author = {Honghui Yin and Zuodong Yang},
     title = {Multiplicity results for a class of concave-convex
elliptic systems involving  sign-changing weight functions},
     journal = {Annales Polonici Mathematici},
     pages = {51--71},
     publisher = {mathdoc},
     volume = {102},
     number = {1},
     year = {2011},
     doi = {10.4064/ap102-1-5},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap102-1-5/}
}