The following elements are optional. They may be included if they are of significance to your use of the source or if they might assist your reader in locating the source. The following list is not exhaustive and you should use your judgement as to what might be helpful.
- City of publication, especially if:
- work was published before 1900
- different versions were released in different cities
- unfamiliar publisher
- Series title (and number in a series, if applicable)
- Unexpected type of work, e.g. a transcript, a lecture heard in person
- Date of access - especially for sources with no date of publication