After he proposed to Marina Durmanova and was rejected, Daniel Veen, a character in ADA, decides to air his feelings and sets off "in a counter-Fogg direction on a triple trip round the globe" (1.1). According to Vivian Darkbloom, the author of "Notes to ADA," Phileas Fogg is the hero of Jules Verne's Around the World in Eighty Days. As to a triple circumnavigation, it is mentioned (along with Uzun Ada, a port on the Caspian sea, between which and Peking the invented Grand Transasiatic railway runs) in another Jules Verne novel, Claudius Bombarnac (http://www.readbookonline.net/title/15308/):
And in a voice like a husky clarinet the actor struck up the well-known air [my emphasis] from the Cloches de Corneville:*
"I thrice have been around the world."
Adding, for the baron's benefit:
"He will not do the half." (end of chapter 9)
There are, of course, more allusions to Jules Verne's novels, including The Children of Captain Grant, in ADA. Cape Horn in Terra del Fuega is known on Antiterra as Captain Grant's Horn (2.1). Ada is said to have read Captain Grant's Microgalaxies at the age of ten or eleven (1.35).