Yorkshire Volunteers ended in 1993.
Yorkshire Volunteers was created in 1967.
Rifle Volunteers ended in 2007.
Olongapo Volunteers ended in 2002.
Yorkshire Traction ended in 2005.
Yorkshire Electricity ended in 1997.
Yorkshire Factory Times ended in 1926.
East Yorkshire Regiment ended in 1958.
South Yorkshire Railway ended in 1864.
West Yorkshire County Council ended in 1986.
Well, honey, to write possessive volunteers, you just add an apostrophe and an "s" at the end of the word "volunteers." So it becomes "volunteers'." That's all there is to it, dear. Next question!
Yugoslav volunteers in the Spanish Civil War ended in 1938.
King's Own Yorkshire Light Infantry ended in 1968.