
* Foundations of Statistical Natural Language Processing by Manning and Schuetze [0]
* Statistical Methods for Speech Recognition by Jelinek [1]
* Spoken Language Processing: A Guide to Theory, Algorithm, and System Development by Huang, Acero and Hon [2]
In particular, Statistical Methods for Speech Recognition is a book you could expect to see on the shelves of most people in the field.
[0] https://www.amazon.com/Foundations-Statistical-Natural-Langu...
[1] https://www.amazon.com/Statistical-Methods-Recognition-Langu...
[2] https://www.amazon.com/Spoken-Language-Processing-Algorithm-...
The book I grabbed was "Spoken Language Processing", Huang Acero, Hon (ISBN 0-13-022616-5) and I counted 88 characters per line. The book is still very readable, despite exceeding the claimed 70-odd character limit for books/columns. Another book sitting next to it (a numerical mathematics textbook) had 82 characters per line.
Granted, the limit of no more than 70 characters per line applies if whitespace and punctuation aren't counted, but that's never done with hard limits in digital documents either, so...