Catching a Mathematical Error Using Haskell’s Type System

I believe the paper the author is referring to is

Franks, John. "Flow equivalences of subshifts of finite type." Ergodic Theory and Dynamical Systems (1984). 4:53-66. Cambridge University Press.

Also, minor errors in mathematics papers are not uncommon. Usually, they are fixed and included in a later edition of the journal as "Errata to [name of paper]." The main purpose of the refereeing process is to detect game-breaking errors such as a missed condition on a theorem used or a misapplication of a tricky technique (usually from another field of mathematics). Interestingly enough, from what I've seen, budding mathematicians actually make a lot of errors that are similar to that of novice programmers (e.g. off-by-one errors in induction, forgetting about boundary conditions).