The article from Reuters about the Titanic steering mistake has only one source in it. Lousie Patten, the woman who revealed the secret of a steering error as the reason the ship hit an iceberg, is mentioned in almost every paragraph.
She is quoted directly once, while the rest of the interview was describe indirectly or paraphrased.
It is explained where she got her information, but the article is written in such a way that the what that she reveals isn't taken as the truth or a lie. It is written objectively to give the reader the means to think for themselves.
The attributions to Patten are very well laid out. It's easy to follow and effectively used.