question: What is the date of death of Tsarevna Catherine Ivanovna Of Russia's mother?
context: [["Bill Smith (footballer, born 1897)", ["William Thomas Smith( born 9 April 1897, date of death unknown) was an English professional footballer."]], ["Abdul-Vahed Niyazov", ["' of Russia."]], ["Tsarevna Catherine Ivanovna of Russia", ["Tsarevna Catherine Ivanovna of Russia (20 October 1691 \u2013 14 June 1733) was a daughter of Tsar Ivan V and Praskovia Saltykova, eldest sister of Empress Anna of Russia and niece of Peter the Great.", "By her marriage, she was a Duchess of Mecklenburg-Schwerin."]], ["Etan Boritzer", ["Etan Boritzer( born 1950) is an American writer of children \u2019s literature who is best known for his book\" What is God?\" first published in 1989.", "His best selling\" What is?\" illustrated children's book series on character education and difficult subjects for children is a popular teaching guide for parents, teachers and child- life professionals.", "Boritzer gained national critical acclaim after\" What is God?\" was published in 1989 although the book has caused controversy from religious fundamentalists for its universalist views.", "The other current books in the\" What is?\" series include", "What is Love?,", "What is Death?,", "What is Beautiful?,", "What is Funny?,", "What is Right?,", "What is Peace?,", "What is Money?,", "What is Dreaming?,", "What is a Friend?,", "What is True?,", "What is a Family?,", "What is a Feeling?\"", "The series is now also translated into 15 languages.", "Boritzer was first published in 1963 at the age of 13 when he wrote an essay in his English class at Wade Junior High School in the Bronx, New York on the assassination of John F. Kennedy.", "His essay was included in a special anthology by New York City public school children compiled and published by the New York City Department of Education.", "Boritzer now lives in Venice, California and maintains his publishing office there also.", "He has helped numerous other authors to get published through\" How to Get Your Book Published!\" programs.", "Boritzer is also a yoga teacher who teaches regular classes locally and guest- teaches nationally.", "He is also recognized nationally as an erudite speaker on\" The Teachings of the Buddha.\""]], ["Harry Wainwright (footballer)", ["Harry Wainwright( born 1899; date of death unknown) was an English footballer."]], ["Thomas Scott (diver)", ["Thomas Scott( 1907- date of death unknown) was an English diver."]], ["Theodred II (Bishop of Elmham)", ["Theodred II was a medieval Bishop of Elmham.", "The date of Theodred's consecration unknown, but the date of his death was sometime between 995 and 997."]], ["Praskovia Saltykova", ["Praskovia Fyodorovna Saltykova  (12 October 1664 \u2013 13 October 1723) was the tsaritsa of Russia as the only wife of Ivan V of Russia.", "She was the mother of Empress Anna of Russia.", "She played an important part as the most senior woman of the Russian court in 1698\u20131712."]], ["Princess Catherine Ivanovna of Russia", ["Princess Catherine Ivanovna of Russia( 12 July 1915( O.S.) \u2013 13 March 2007) was a great- great- granddaughter of Tsar Nicholas I of Russia and a niece of King Alexander I of Yugoslavia.", "She was the last member of the Imperial Family to be born before the fall of the dynasty."]], ["Matryona Balk", ["Matryona Ivanovna Balk( n\u00e9e Modesta Mons; fl. 1718), was a Russian courtier.", "She was a lady- in- waiting and confidant of Catherine I of Russia, Ober- Hofmeisterin of Tsarevna Catherine Ivanovna of Russia and sister of Anna Mons.", "She was accused in 1718 for having assisted the empress in her love affair with Willem Mons."]]]
supporting_facts: [["Tsarevna Catherine Ivanovna of Russia", 0], ["Praskovia Saltykova", 0]]
evidences: [["Tsarevna Catherine Ivanovna of Russia", "mother", "Praskovia Saltykova"], ["Praskovia Saltykova", "date of death", "13 October 1723"]]
answer: 13 October 1723