Many Ph.D. programs have an arrangement with ProQuest whereby a copy of each dissertation (or Ph.D. thesis) is deposited with ProQuest and made available for ordering. One way to find them is by going to the ProQuest website. Another is to search using MathSciNet!
ProQuest handles dissertations and theses in many, many disciplines. Their classification scheme is necessarily coarser than what we use at Mathematical Reviews. We receive bibliographic data about the theses published in Mathematics, Applied Mathematics and Statistics. When we receive the data from ProQuest, there are no Mathematics Subject Classifications (MSCs) associated to them. So we have used the “MSC” field in the MathSciNet search as the placeholder for the “Thesis” flag.
So how do you find a thesis? One way is just to do a search in MathSciNet and have the thesis turn up as part of the search. However, if you really want to find just the thesis, then you have to use one of MathSciNet’s hidden tricks. Here is an example.
A famous thesis in number theory is John Tate’s, written under the direction of Emil Artin at Princeton. Wikipedia even has its own entry for it! Here is how to find it in MathSciNet. In the Author field, enter “tate, jo*”. In the MSC Primary/Secondary field, enter “thesis”. (It also works in the MSC Primary field.)
The result is:
If you click the link Thesis, you jump to the ProQuest website:
From here, you can order a copy, either as a PDF download or in one of several printed formats.
MathSciNet began listing ProQuest theses and dissertations in October 2010. As of July 5, 2015, there are 76,413 such items in MathSciNet. For the year 2014, we loaded 1,950 theses into our database. (A few more may drift in still.) ProQuest delivers the data to us on a monthly basis.
There is also information about older theses. For the year 1885, the search
produces the results
Note, though, that actual copies of many of the old theses may not be available.
So if you are looking for a thesis, even your own, trying using this little-known feature of MathSciNet!
Update [October 19, 2016]: French theses from the “Between Two Wars” period have been added to MathSciNet, thanks to NUMDAM. You can still find them by using “thesis” in the MSC field. If you want to specifically find one of these theses, then put the work “numdam” in the Anywhere field.