Citation: Boy, Insan; Sch\"afer, Gerd; Kniep, R\"udiger (2001). Crystal structure of sodium nickel diaqua catena-[monoboro-diphosphate] monohydrate, NaNi(H~2~O)~2~[BP~2~O~8~] · H~2~O, at 293 K and 198 K. Zeitschrift f\"ur Kristallographie - New Crystal Structures, 216, pp. 11-12.