Poly[[diaqua(1,10-phenanthroline-κ<sup>2</sup><i>N</i>,<i>N</i>′)(μ<sub>3</sub>-4-sulfonatobenzene-1,2-dicarboxylato-κ<sup>4</sup><i>O</i><sup>1</sup>:<i>O</i><sup>2</sup>,<i>O</i><sup>2′</sup>:<i>O</i><sup>4</sup>)erbium(III)] dihydrate]
Acta crystallographica. Section E