[OL]Behling surname in Oldenburg Area

I have recently learned my great grand parents Heinrich Behling b.4 Jul
1857 in the Oldenburg area, he died in Minneapolis,MN 24Dec 1909 his wife
Reka Kolls(Kohls) b 4 Apr 1864 d. 11 Jul 1929 also in Minneapolis.
They had three sons Carl William, Robert Paul, Henry Albert at one time all
resided in Minneapolis.
My search has lead me this close any knowledge information or where I might
search next, is deeply appreciated.

Thankyou,

Richard G. Behling
Plymouth,MN
rbehling0535@attbi.com