@article{GDZPPN002343827,
title = {Problem 12},
journal = {Mathematica Scandinavica},
volume = {3},
year = {1955},
pages = {171-171},
zbl = {0065.30303},
url = {http://dml.mathdoc.fr/item/GDZPPN002343827}
}
BEURLING, ARNE. Problem 12. Mathematica Scandinavica, Tome 3 (1955) p. 171. http://gdmltest.u-ga.fr/item/GDZPPN002343827/