claim: The current Duke of York has been unmarried since his 1996 divorce.
evidence: Edwin Robert Bickerstaff -LRB- 20 November 1920 -- 23 November 2008 -RRB- , was a British neurologist .. He is best remembered for describing Bickerstaff 's encephalitis and a subtype of migraine -LRB- basilar migraine -RRB- that is sometimes called `` Bickerstaff 's migraine '' .. migraine. migraine