It's stated that the first Mark Caine novel was set in Instanbul. (The Perfect Operation (1969) confirmed this was "Istanbul Iliad".) A copy of King's "Index Finger Left Hand" is seen, whilst Jason cites an example of Mark Caine's willful misinformation featured in "From China Yours Sincerely".
Jason quotes Act III Scene I of William Shakespeare's 1599 play "Julius Caesar": "Et tu, Brute? Then fall, Caesar!"
According to Ryland, "[Jason's] mother was a French countess whilst his father ... was descended from an eminent family of the exiled Muscovite dynasty ... His American family connections have produced not one but two Presidents this century."