The most common organizational principle of bibliographies is to list single entries in alphabetical order of the author's surname. There are, however, other questions to be considered which will be discussed below.
Multiple works by an author
What should you do if you have to list more than one work by a particular author? You will need to decide whether to arrange your entries alphabetically by title or chronologically. In the case of primary literature, it may, in certain cases, make sense to order your entries in choronological order, whereas multiple secondary works of one author should almost always be organized alphabetically. Moreover, if translations are added, you will have to decide once more, where to place them. If, for example, you have opted to put your primary sources in chronological order, do you then maintain a chronological system for the translations, or do you let the translations follow directly after the original? More often than not, the latter is preferable. But the choice is up to you - use your intelligence and consider the relevance of a chronological organization within the overall framework of your bibliography and research project. Whichever way you choose, explain to the reader briefly how and why you organized your bibliography in a certain way.
Translations: to include them or not and how to list them?
If and where to place translations within your bibliography depends first of all on whether you chose to use as your research material translations rather than originals, to work with both, or to exclude translations altogether. However, as you are most likely going to be a PhD student enroled in a Romance studies department, it will be expected that you will predominantly study your sources in their original language. This concerns primary sources as well as secondary sources. However, if for example, you are examining the process of translation itself, or the reception of specific authors in different countries, then the inclusion of translations and your method of listing them within your bibliography obviously becomes a crucial point.
The scenario is slightly different again if you are doing a PhD concerned with Romance culture, but you are enrolled in a philosophy, film, theatre or arts department, where the focus is slightly less on language than on theory. The exmination of your dissertation might then be more leniant towards the use of translations. However, you may be doing a PhD on the French filmmaker Chris Marker, in which case you will find that most of the literature will be in French and you might even only find out that your examiner will be based in a French department. She or he may then appreciate your work with French sources rather than their translations.
So once you have decided whether to include translations in your bibliography or not, you must again decide on a method of how to list them. The most common option would be to list them after the original source. But there might be other options. If for example you have worked with many translations of one particular author, then you may want to group original sources separately from translations. Your choice should be informed by the contents and methodology of your thesis. And the more complex your choice of structuring your bibliography is, the more important to make it transparent to the reader: explain it in one or two sentences. For further discussion of bibliographical questions directly connected with the use of Romance languages, click here: Bibliography and Romance languages.
You may have mentioned or consulted different editions of one particular work for your thesis. Again, you will have to take a decision how to list them, especially if the entries of one author are in chronological and not in alphabetical order, as different editions of one and the same work may become separated within a chronological structure.
Subsections within your bibliography
Granted that your actual research topic and its structure will automatically give you a sense of what the important headings of your bibliography are, the most common pattern in the majority of PhD bibliographies is a distinction between: