CRYSTAL STRUCTURE OF POLY[?2-AQUA-AQUA(?2-4-NITRO-2,5,6-TRIOXO-1,2,5,6-TETRAHYDRO-PYRIDIN-3-OLATO)HEMI-?4-OXALATO-BARIUM(II)] Article Alabada Rusul, Kovalchukova Olga, Polyakova Irina, Strashnova Svetlana, Sergienko Vladimir Acta Crystallographica Section E: Crystallographic Communications. International Union of Crystallography. 2015. P. 459-462