From the record
“The Thomas Ashcroft Ranch, in Harding County, South Dakota near Buffalo was listed on the National Register of Historic Places in 1987.”
Wikipedia article Thomas Ashcroft Ranch, CC BY-SA 4.0.
One of 13 National Register listings published here for Harding County · listed in 1987 · category: Building · built in 1910.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service