Reliable theses and dissertations

Where to find theses and dissertations from official sources, free and legally, and how to check whether a text is used by the community. Every address below belongs to a university, a national library, a government or a scientific institution.

International

1. OATD: search millions of open-access theses and dissertations from all over the world, at oatd.org.
2. NDLTD: the international network of digital libraries of theses, at ndltd.org.
3. BASE: Bielefeld University's academic search engine; use the filter "Document type → thesis", at base-search.net.
4. CORE: gathers open-access texts from repositories worldwide, at core.ac.uk.
5. ProQuest Dissertations & Theses Global: the largest thesis database, mainly from the United States. It is paid; access is through your university library when it subscribes (learn more).
6. arXiv: many authors post their thesis there, at arxiv.org.
7. Mathematics Genealogy Project: lists the thesis title, university and advisor of each doctor in mathematics, at mathgenealogy.org.
8. Google Scholar: finds theses, but always check that the link leads to the official repository, at scholar.google.com.

Europe

9. Europe in general: DART-Europe, the European thesis portal, at dart-europe.org.
10. Germany: every German thesis is deposited at the Deutsche Nationalbibliothek, at dnb.de.
11. Kassel: the official repository of the University of Kassel is KOBRA, at kobra.uni-kassel.de.
12. France: the national catalogue of doctoral theses, at theses.fr.
13. France (full text): the thesis portal of the HAL open archive, at theses.hal.science.
14. Spain: the official TESEO database of the Ministry of Education, at educacion.gob.es/teseo.
15. Catalonia: the TDX open-access thesis repository, at tdx.cat.
16. Portugal: RCAAP gathers the country's open-access scientific repositories, at rcaap.pt.
17. Italy: doctoral theses are deposited by law at the National Central Libraries of Florence and Rome, at bncf.firenze.sbn.it; many universities also have their own repositories.
18. Switzerland: the ETH Zurich Research Collection, at research-collection.ethz.ch.
19. Sweden and the Nordic countries: the DiVA portal, at diva-portal.org.
20. United Kingdom (Cambridge): the Apollo repository, at repository.cam.ac.uk.
21. United Kingdom (Oxford): the ORA repository, at ora.ox.ac.uk.

The Americas

22. United States (MIT): the DSpace@MIT repository, at dspace.mit.edu.
23. Canada: the Theses Canada service of the national library (Library and Archives Canada), at library-archives.canada.ca.
24. Latin America: the LA Referencia network, which gathers repositories from several countries, at lareferencia.info.
25. Mexico: UNAM's thesis catalogue, TESIUNAM, at tesiunam.dgb.unam.mx.

Asia and Oceania

26. India: the national repository Shodhganga, at shodhganga.inflibnet.ac.in.
27. Japan: CiNii Research, which includes Japanese doctoral theses, at cir.nii.ac.jp.
28. Australia: Trove, from the National Library of Australia, at trove.nla.gov.au.

Brazil

29. Brazil in general: the Brazilian Digital Library of Theses and Dissertations (BDTD), from IBICT, at bdtd.ibict.br.
30. CAPES catalogue: every thesis and dissertation defended in Brazilian graduate programmes, at catalogodeteses.capes.gov.br.
31. Oasisbr: the Brazilian open-access portal, gathering repositories from the whole country, at oasisbr.ibict.br.
32. UnB: the institutional repository of the University of Brasília (RIUnB), at repositorio.unb.br.
33. USP: the Digital Library of Theses and Dissertations of the University of São Paulo, at teses.usp.br.
34. IMPA: dissertations and theses defended at the institute are listed in the graduate section of its website, at impa.br.
35. SciELO: for the papers that often grow out of theses, at scielo.org.
36. Lattes: shows the publications, supervisions and examination committees of every Brazilian researcher, at lattes.cnpq.br.

How to get access for free, within the law

37. CAPES Journal Portal (Brazil): sign in with your university's institutional login (CAFe) and read paid journals and databases for free, at periodicos.capes.gov.br.
38. Unpaywall: a browser extension that shows, when you open a paper, whether a legal free version exists, at unpaywall.org.
39. Open Access Button: looks for legal free versions of papers and, if there are none, helps you request them from the author, at openaccessbutton.org.
40. DOAJ: the official directory of open-access scientific journals, at doaj.org.
41. COMUT (IBICT, Brazil): the Brazilian document-delivery service, which obtains copies of documents from other libraries within the law, at comut.ibict.br.
42. Ask the author: writing to the author for a copy is legal, common and almost always welcome. The e-mail address is usually in the paper itself or on the researcher's web page.
43. Your university library: interlibrary loan can obtain books and theses that your institution does not hold.

How to check whether a text is reliable

44. Citations: see how many times the text has been cited in MathSciNet (through institutional access) or in zbMATH Open (free).
45. Did it become a paper? Check whether the results of the thesis were later published in a peer-reviewed journal.
46. Advisor and committee: check who supervised and who examined the work, in the Mathematics Genealogy Project or, for Brazil, in Lattes.
47. Permanent link: prefer citing the official repository address, with a DOI or Handle, which does not change over time.
48. Licence: before sharing the PDF, check the licence stated in the repository (for example, Creative Commons).

An important caution

49. Avoid unofficial websites: sites that distribute texts without authorization infringe copyright and may carry viruses. The sources in this list are enough to find almost everything freely and legally.