@article{10_4064_fm229_3_2,
     author = {Sy-David Friedman and Liuzhen Wu and Lyubomyr Zdomskyy},
     title = {$\Delta _1${-Definability} of the non-stationary ideal at successor cardinals},
     journal = {Fundamenta Mathematicae},
     pages = {231--254},
     publisher = {mathdoc},
     volume = {229},
     number = {3},
     year = {2015},
     doi = {10.4064/fm229-3-2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm229-3-2/}
}