<span>The three situations, when attributions are not necessary, are: 1. Common knowledge. If the information
is a well-known fact it's widely used and doesn't represent a particular
author. common 2. Background information. If there are many
sources that provide the same information, so it's not an idea of a particular
author. 3. Observation. If the
information is your own idea, a result of your own research and observation.</span>