The story "Mountain hunt for ex-LAPD cop enters 4th day" in The Seattle Times used a handful of sources. Some of these sources were named and a few remained unnamed.
The Seattle Times used six different sources. The sources named are the police chief, one of the captain's that was on the board who took away Dorner's badge, a store employee who found evidence from Dorner and online postings from Dorner. The two sources unnamed are a captain who was said to be a target of Dorner and law enforcement officers who had found evidence dealing with Dorner's disappearance.
The sources are scattered throughout the story. Each source goes with the fact block that it relates to. The sources are scattered throughout to help make the story flow better and to give credibility to different aspects of the story. All the information provided is given by people.
Most of the time when the reporter is attributing someone they introduce the person and then the following paragraph will be a direct quote from them. There are a few times when the reporter attributes a new person at the end of the quote with their title, but the quote still starts off the paragraph. When the reporter refers to the captain who is unnamed they explain that the captain is a target of the suspect.
I think this reporter's use of attribution is effective. When there are longer quotes the reporter introduces the person beforehand. If the quote is shorter the person is usually named after the quote. This allows the reader to know who is speaking, rather than making them guess. The way the reporter attributed the unnamed captain was effective by giving a short, clear and concise explanation as to why they weren't named.