Martin Ball 
Theoretical Linguistics and Disordered Language (RLE Linguistics B: Grammar) [PDF ebook] 

The rapid increase of interest in disordered speech and language among linguists over the past decade or so has resulted in many books of practical help to speech pathologists in terms of assessment and remediation. Little, however, has appeared to examine the theoretical implications of the interaction between these two fields. This book aims to fill this gap, by showing how speech pathology can inform linguistic theory and vice versa.