A. Abragam was formerly Professeur au Collège de France, Paris.; B. Bleaney was formerly Dr Lee's Professor Emeritus of Experimental Philosophy, University of Oxford.
It must be abundantly clear that I recommend this book wholeheartedly as an absolute classic, a must-have for any university or research library and for any person (teacher, student or researcher, experienced or otherwise) with any interest in the physics of defects in crystalline materials. * Enda McGlynn, Contemporary Physics *