@article{AA_2020_32_4_a2,
     author = {L. El Hajj and H. Shahgholian},
     title = {Remarks on the convexity of free boundaries {(Scalar} and system cases)},
     journal = {Algebra i analiz},
     pages = {146--165},
     publisher = {mathdoc},
     volume = {32},
     number = {4},
     year = {2020},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AA_2020_32_4_a2/}
}