Nearly 90 police detectives, some from as far away as Arizona, have converged on Fayetteville this week to learn from the author of a book billed as the bible of homicide investigation.

Vernon Geberth, a retired lieutenant commander from the New York City Police Department, brushes off the appellation for his book, "Practical Homicide Investigation."

"I don't call it 'The Bible,' " he said. "I'm not arrogant enough to do that."

Geberth refers to it as a textbook. One that has grown to more than 1,000 pages as he has revised and expanded on it since the first edition was published in the 1980s.

"He teaches 'outside the box' techniques for investigating homicides," said Amber House, a community relations specialist for the Fayetteville Police Department.

The department sponsored the visit, one that the officers paid $500 each to attend. Geberth said he was grateful and honored to be invited.

House said some agencies require their homicide detectives to attend Geberth's seminars.

Today is the last day of Geberth's three-day seminar, at the Holiday Inn Bordeaux in Fayetteville. Topics covered include investigative techniques; a growing trend in sex-related murders; and how detectives can use detailed criminal case histories to work through a case.

The Internet, Geberth said, is fostering sex-related crimes.

"Since the beginning of time we've had people who are 'different,' " he said. But now they access images and pornography online and it feeds their desires to commit sexually related homicides, he said.

"It's like a brain cocktail. It's pleasing (to them)."

"... And if you're the type of person who is a psychopath or a sexual offender, this will give you information as to how to construct your assault," he added.

Geberth conducts his seminars and works as a consultant for law enforcement. He says he will never work for a defense lawyer.

He said he has followed one Fayetteville-area homicide case since the 1980s: The Eastburn murders. Timothy B. Hennis was acquitted of the crime in 1989 in civilian court and then convicted of this year at an Army court-martial.

The case, in which an Air Force wife and two of her children were stabbed to death, was re-opened in 2006 after a DNA test brought the focus back onto Hennis.

"When the acquittal came down and they told me, I said, 'Oh my God, that's wrong. That is so wrong,' " he said. He was glad to see the conviction this year and had Robert Bittle, one of the original detectives, present the case on Tuesday.