* Ibid. (Latin for "in the same place"): This abbreviation refers to the immediately preceding source, even if there are multiple sources cited in between.
* Idem. (Latin for "the same"): This abbreviation is similar to "ibid." but is used when referring to the same author but a different work.
* Op. cit. (Latin for "in the work cited"): This abbreviation is used when referring to a source that was cited earlier in the text, but not necessarily the immediately preceding source. You will need to provide the page number for the source you are referring to.
* Loc. cit. (Latin for "in the place cited"): This abbreviation is similar to "op. cit." but is used when referring to the exact same page number as the previous citation.
Example:
> The author discusses the rise of social media in his book. (First citation)
> Jones argues that social media has had a profound impact on society. (Second citation)
> Ibid. (This refers to the same source as the previous sentence - Jones' book)
> Op. cit., p. 12. (This refers to a previous citation of Jones' book, but not necessarily the immediately preceding one, and specifies the page number)
Remember, the specific abbreviations and how they are used can vary depending on the style guide being followed. It's always best to consult the style guide you are using for specific guidance.