found: Work cat.: Bolton, M. Seven centuries of service : the lives of the Dukes of York, 1385 to today, 2013.
found: Royal Central website, viewed Jan. 30, 2018:blogs, "Royal Dukedoms: Duke of York" posted 11 Nov. 2016 (Held by eleven noted, and often notorious, male royals over the past 500 years, the Duke of York title has traditionally been granted to the second son of the English monarch and has been created eight times since its original inception. Originating in the fourteenth century the title was named for the city of York in the North of England)
found: Wikipedia, viewed Jan. 30, 2018(The Duke of York is a title of nobility in the peerage of the United Kingdom. Since the 15th century, it has, when granted, usually been given to the second son of English (later British) monarchs)
