Caroline Minuscule is the first in Andrew Taylor's William Dougal series, and it's on sale right now at Kindle UK for £0.99. This was Taylor's first mystery, and per
SYKM, it won a New Blood Dagger, and was a finalist for an Edgar for Best First Novel. I read this a long time ago in DTB, while I myself was in grad school (Dougal is a grad student, although in a very different way), and enjoyed it - although it's not quite the academic mystery you might expect...
Kindle UK:
https://www.amazon.co.uk/dp/B008K5TDDM
Kindle UK/Smile:
https://smile.amazon.co.uk/dp/B008K5TDDM