I purchased in Jacksonville, OR, the subject undated studio portrait of a middle-aged woman, identified on the back of the print:
"Nell Armstrong 400 E--Richmond--"
A possible candidate for this individual is Nellie Edith Cook, born 22 Sep 1913, died Mar 2006 in Prineville, OR. She married Arlie Armstrong, born 7 Dec 1900 in Indian Territory, OK, the son of James Armstrong. The couple had two children, including Edward L. Armstrong.