Has there ever been a successful copyright infringement suit against someone using a small amount of a protected work in an academic publication?
One case in a similar direction is Sundeman v. The Seajay Society.  A researcher included quotations from an unpublished work in a presentation; this was upheld as fair use.  There's some discussion of the case and the outcome from the Columbia copyright office (have to scroll down a little bit).  There are some other related cases listed on the same page, e.g. involving fair use of copyrighted images in less academic publications.