@article{CMJ_1998__48_1_a4, author = {Junnila, H. J. K. and K\"unzi, H. P. A.}, title = {Characterizations of absolute $F_{\sigma\delta}$-sets}, journal = {Czechoslovak Mathematical Journal}, pages = {55--64}, publisher = {mathdoc}, volume = {48}, number = {1}, year = {1998}, mrnumber = {1614072}, zbl = {0926.54018}, language = {en}, url = {https://geodesic-test.mathdoc.fr/item/CMJ_1998__48_1_a4/} }