There are two main ways to locate dissertations in the library catalog. The first method uses the Dissertations & Theses filter in Quicksearch, and the second takes you to ProQuest Dissertations and Theses Global. The filter in QuickSearch (and the results on Articles+ that it brings you to) have fewer advanced options than ProQuest Dissertations and Theses Global, so the one you use really depends on how complex your search is.

The Quicksearch Method

There is a general filter for dissertations and theses in Quicksearch, which will take you to the Articles+ interface. Here, we are searching for Seneca grammar, an excellent search because we can talk about narrowing down our search, too.

On the Articles+ screen, we can see a clear problem here. There are so many people who have written about the Roman man named Seneca that it's hard to find information about the Seneca language! We have several options that we could try, including narrowing down by discipline. However, for this search, let's keep it simple.

There are a few things we can try in Articles+ to narrow down our results. First, we could use the Quick Look feature for the second article in the screenshot — the only one in the top 3 about the Seneca language — to identify keywords of note. Iroquoian is an example term that we could add to the search, but not all dissertations will mention the language family in the summary.

We know that the Roman author Seneca wrote in Latin. We also know that sometimes, Greek might come up — these are both Classical Mediterranean languages, and someone might talk about the Greek reading of Seneca without mentioning Latin at all in a summary or abstract.

In Articles+, the minus sign will remove terms from a search. (Note: In other tools, a NOT in uppercase may do the same thing. It really depends!)

This results set looks much cleaner! In addition to dissertations that are about some aspect of the Seneca language, there are also a few dissertations that mention Seneca comparatively during a study of another Native American language.

ProQuest Dissertations and Theses Global

ProQuest Dissertations and Theses Global has full-text coverage from 1743 to the present for many dissertations in the United States and from around the world. Many graduate students are required to deposit their dissertations here or in another database (see the list to the right for other places to search).

The best way to access this resource is to use the QuickSearch Databases list. Once there, search for the name of the database. (Searching for "ProQuest dissertations" will also work.) The above screenshot shows a search that started on the main library website. All you have to do is click Databases just below the search box on the results screen to narrow down to databases. 

I have searched for Seneca grammar using the free-text search. Note that many irrelevant results are in this search because the language shares a name with a famous historical figure. To narrow down to more relevant results, use the subject filter to limit to Linguistics. This will improve the results set.

After limiting the search, many of the results are about Seneca and other Haudenosaunee languages. While they are about aspects of grammar, we need to think about the words we are using in our search.

If we change our search to "a grammar of" AND Seneca AND language, the quotation marks will search the phrase a grammar of; the Boolean operator AND will let the database know that we want the words Seneca and language included. It's useful to find common phrases in titles of grammars to narrow down one's search. We could also search for the phrase "Seneca grammar" using an OR operator, creating this search: (("a grammar of" AND Seneca) OR "Seneca grammar") AND language.

Without picking a specific language, as long as we make sure we apply the Subject filter so we are limiting the results to Linguistics, one can also search for the phrase "a grammar of" AND language, which will (usually) show us documents that are grammars of various languages.

We have done all of this with the basic search. If we used the Advanced Search, we could limit our search to identify words in titles, abstracts, and so on.

This search for a grammar of the Tuscarora language retrieves one result.

ProQuest Dissertations & Theses (PQDT) provides a very comprehensive collection of dissertations and theses and is the official digital dissertations archive for the Library of Congress. The database provides full text for most dissertations after 1997, and older materials that have not been digitized are available for purchase as printed copies.