I was a reader of Sawyer's articles in the US Internal Auditing magazine in the 1980s. His cerebral approach, courage and independence from management while also championing the organisation's needs (a difficult balance) inspired me to pursue a career in internal audit which I have now been doing for the past 30 years. What Sawyer championed then is still relevant today as too many internal audit departments perform poorly due to lack of courage to challenge management.
These days I am myself a contributor of articles to US Internal Auditing magazine, all of which are here on my Researchgate profile.
Sawyer's Internal Auditing: The Practice of Modern Internal Auditing, 6th edition in 2012, is an update of his classic book on internal auditing. He has brought in other authoritative authors and contributors and given its length (approximately 1500 pages) and extensive breadth of coverage this continues to be a great resource book. Further, it is a testimonial to the quality of this outstanding book that it is published by the Institute of Internal Auditors.