DH
David Harley
David Harley is a former IT security researcher, author/editor and consultant living in the United Kingdom, known for his books on and research into malware, Mac security, anti-malware product testing and management of email abuse.
Excerpt from Wikipedia, available under CC BY-SA 4.0.
Books

Viruses Revealed
2001
ISBN 9780072130904
OS X Exploits and Defense
2008
ISBN 9780080558769