Recently I open this book to look up a certain theorem and saw something peculiar about the acknowledgments I've never notice before:
I thank Ron Infante and Peter Pappas for assisting with the proof reading and for useful suggestions and corrections. I also thank Gimli Khazad for his corrections.
The first two seem to be the (real) mathematicians Ronald P. Infante and Peter Chris Pappas but the third name is quite suspicious: everything I can find about this name is either related to the famous dwarf from Lord of the Rings or a small town in Canada. What's even more funny is that the surname "Khazad", in the fictional dwarven language created by Tolkien, means "dwarves".
Is Serge Lang thanking Gimli the dwarf? Was he known to make pratical jokes? This is too much of a coincidence.
EDIT: Here's a link to the book. The acknowledgments are after the foreword.