@article{10_4064_sm_65_3_313_335,
     author = {Calixto Calder\'on},
     title = {On a singular integral},
     journal = {Studia Mathematica},
     pages = {313--335},
     year = {1979},
     volume = {65},
     number = {3},
     doi = {10.4064/sm-65-3-313-335},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm-65-3-313-335/}
}