booktitle

To cite an incollection, i.e., a part of a book/collection with its own title, or to give a title to an article, part of an inproceedings, the booktitle-field is used to distinguish. At the same time, title contains the title of the book, or incproceedings.

Example

@incollection{Mueller2014The,
  ...
  booktitle={ ... }
  ...
}