@article{CM_1994__92_3_249_0,
     author = {Urbanowicz, Jerzy},
     title = {On diophantine equations involving sums of powers with quadratic characters as coefficients, {I}},
     journal = {Compositio Mathematica},
     pages = {249--271},
     publisher = {Kluwer Academic Publishers},
     volume = {92},
     number = {3},
     year = {1994},
     mrnumber = {1286126},
     zbl = {0810.11017},
     language = {en},
     url = {http://www.numdam.org/item/CM_1994__92_3_249_0/}
}