Weisstein, Eric W., "(({title))}" ("(({title2))}") at MathWorld.
((MathWorld2|title = title|urlname = urlname|title2 = title2|urlname2 = urlname2))
where all four parameters must be in title case.
((MathWorld2|title = Prime Number|urlname = PrimeNumber|title2 = Primes|urlname2 = Primes))
((MathWorld |title=Prime Number
|id=PrimeNumber |access-date=((subst:TODAY))))