Sometimes you find a source with no title. For instance, if you find an image without a title. In this case, you should create a brief description of the work and place it in square brackets: [ ]. You must provide the author and publication date, describe the work in square brackets, and otherwise follow the description of the source type that is most similar.
Jobs, S. (2010). [User manual for e-reader]. Apple.
You can find square brackets on