Fyodor Vasilyev

Feodor Vassilyev (, older spelling: ;

The data about Vassilyev's children are included in the Guinness Book of World Records. and in an 1834 book by , Saint Petersburg Panorama.

Skepticism Several published sources raised doubts as to the veracity of these statements. According to a 1933 article by Julia Bell in Biometrika, a 1790 book of B. F. J. Hermann Statistische Schilderung von Rußland did provide the statements about Feodor Vassilyev's children but "with a caution". Bell also notes that the case was reported by The Lancet in an 1878 article about the study of twins. The Lancet article states that the French Academy of Sciences attempted to verify the statements about Vassilyev's children and contacted "M. Khanikoff of the Imperial Academy of St. Petersburg for advice as to the means they should pursue, but were told by him that all investigation was superfluous, that members of the family still lived in Moscow and that they had been the object of favors from the Government". Bell concludes that Vassilyev's case "must be regarded as under suspicion".

Similarly, in her book Quadruplets and Higher Multiple Births (1989), Marie Clay of the University of Auckland notes: "Sadly, this evasion of proper investigation seems, in retrospect, to have dealt a terminal blow to our chances of ever establishing the true detail of this extraordinary case".