@article{10_4064_ap_20_3_231_244,
     author = {Paulina Pych},
     title = {On some linear operators defined by double integrals},
     journal = {Annales Polonici Mathematici},
     pages = {231--244},
     publisher = {mathdoc},
     volume = {20},
     number = {3},
     year = {1968},
     doi = {10.4064/ap-20-3-231-244},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-20-3-231-244/}
}