I have just graduated from the University of Chicago and no longer have access to online journal resources, but I cannot afford to pay for them directly. Normally, I would be able to access library resources for a small fee in the campus library. However, due to closures due to Covid-19, this is no longer an option.

Previous responses to a similar question often involve physical access to a library, which is impossible for many for the foreseeable future. They also consider some access to online resources, but I was wondering if there were any Covid-specific online resources which have come about given the recent crisis. Even if they are not specific to the crisis, online tools which are accessible now are increasingly important, so would be useful.

• Do you still have VPN from UChicago? That will make it appear as if you are on campus and usually grants journal access. If not, do you still have a departmental unix account (assuming Chicago has one)? It's possible to set up a proxy via a ssh tunnel and this also makes it seem like you are accessing the internet from on campus. – RBega2 Jul 13 at 22:22
• There is an illegal Hub for Sci-ence that provides a lot of journal access, started in Kazakhstan. You shouldn't check it out, though. – David Roberts Jul 14 at 0:19
• @David Roberts: The reason why some people DO NOT post their papers on the arXiv totally escapes me. Probably they write their papers not to be read but for some other purpose. – Alexandre Eremenko Jul 14 at 5:02
• @AlexandreEremenko it's not a .tex file, but it is LaTeX: arxiv.org/e-print/1905.02537 so open it in your favourite editor (more generally, change /abs/ to /format/ in the url of any arXiv paper, and if the source is there, you can get it. I've grabbed good styles and macros this way) – David Roberts Jul 14 at 5:13
• Something else you can try, if the article was published recently and the author is still active, is to email them and simply ask for a copy of the paper. – Mike Shulman Jul 14 at 16:19

Let me try to summarize this long discussion in the comments. There are many free resources.

1. arXiv. It is true that not all mathematicians post their papers on the arXiv, for various reasons. But some of those who don't, post them on their personal sites. There are also other depositories, for example in Europe (see 5 below).

2. NSF depository. NSF's stated policy is that all results of NSF-sponsored research "must be available to the public at most in 1 year since their publication". I checked: the site is somewhat confusing but it works.

3. Many journals are freely available, and many more make their papers available after some time (usually 4-5 years). When you choose a journal to publish your paper, take this into account! Here is a convenient catalog of online journals. I am sure many other libraries have similar catalogs; I find this one convenient. The journals with free access are marked green, with partial access yellow and red. Access may depend on your location or on the date of publication.

4. Finally there are "pirate" sites. Some of them may have huge collections, larger than many university libraries. They frequently change their names and location. Some keywords may be "bookfi" or "genesis" for books, and "sci-hub" for journal articles. (Some of them may be illegal in some countries).

5. A simple search on Google and especially on Google Scholar sometimes finds what you need. It could be a place you do not expect. Some saved/cached copy. Some preprint depository that you do not know. Some personal web site, etc.

6. The very important resource is MathScinet, which unfortunately has no free version. But its German competitor Zentralblatt Math is partially free. Whatever you search there, it gives you only 3 items for free. But by clever choice of search criteria you can obtain amazing results. For really old items, there is also Jahrbuch which is free (it is a subset of Zentralblatt). For new papers, Google Scholar is excellent, especially if you know the author's name and title of the paper. It also sometimes finds you a free copy when available.

EDIT. I asked NSF, and they explained that all NSF-supported papers older than 1 year are really available, though the site is somewhat confusing. One has to click on the title of the paper, and then on a little square which says "pdf".

EDIT 2: I collected some links to free resources on my web page.

• Even if these sites frequently change their names and location, you can usually find a valid URL on their Wikipedia pages. (Your ISP may block that URL, though.) – Federico Poloni Jul 14 at 8:29
• Not just Jahrbuch, but EuDML is excellent for older articles from European journals (hence lots of Springer). It usually gives a link to a free copy if there is one. – David Roberts Jul 14 at 11:30
• Community Wiki? – LSpice Jul 14 at 13:22
• According to a recent press release, Zentralblatt Math will become free by 2021. – JonCC Jul 17 at 22:36
• @JonCC: this is a great news of course. But let us wait and see: I suspect that they may be talking about some reduced free version (of the kind they currently have). – Alexandre Eremenko Jul 17 at 23:11

Some are just too shy to actually give the concrete answer, so here it is:

# Sci-Hub: https://sci-hub.st

Pro-tip: Go to the WikipediA page of Sci-Hub to keep up with the new domains of Sci-Hub (since they have to constantly change them owing to the cancel culture brought down by academic publishers).

If you're looking for most scientific papers fetched by Sci-Hub check LibGen: https://libgen.is/scimag/

(The pro-tip mentioned above applies here as well)

Pro-tip2: If for whatever reason you can't access that website then you can simply get around this by installing the Tor Browser and accessing it from there.

I wish you fulfilling and safe mathematical readings.

• Sci-Hub is already mentioned in a comment, as well as (indirectly) in Alexandre Eremenko's answer. Directly linking copyright-violating sites on MO is also quite a contentious issue. – Carl-Fredrik Nyberg Brodda Jul 14 at 12:37
• In this case, the OP using sci-hub would not represent a copyright violation. His university has already paid for subscriptions to the journals in question. In general, you are allowed to possess an electronic copy of a resource (book, article, journal) when you have already possessed or paid for a different copy. For example, if I have a copy of Dummit-Foote on my bookshelf in my office, I can legally download a pdf of it. I think the same applies here. – David White Jul 14 at 13:14
• Even when you do have paid access, Sci-Hub is usually faster. Making a publisher's website recognize your institutional subscription can be a ridiculous rigmarole. But with Sci-Hub you just paste in the DoI and up comes the PDF. Perfect. – Tom Leinster Jul 14 at 14:55
• @Carl-FredrikNybergBrodda: The mentions in comments and other answers are euphemistic and unclear; if illegal sites to be discussed at all, it seems better and more professional to do so frankly and explicitly. It’s good to consider the legal and ethical issues, as discussed in the meta question you linked, and to avoid such sites for literature links in ordinary MO questions/answers. But on a question like this one, where the question itself is “what such sites exist”, it seems pretty denialist to avoid them. – Peter LeFanu Lumsdaine Jul 14 at 16:39
• @PeterLeFanuLumsdaine Absolutely. Plus, let's not be too hasty in calling Sci-Hub "illegal". None of us are lawyers. Just because someone like an Elsevier spokesperson claims it's illegal, doesn't mean it is. Just because some ISPs have been pressured to block access, doesn't mean it's illegal. And just because it's illegal in your country, doesn't mean it's illegal in other people's. – Tom Leinster Jul 14 at 18:33

The two answers posted summarize most of the comments, but miss two important ones.

1. Go to the University of Chicago library website. Click "My Account" in the upper left. Login with your University of Chicago credentials. Contact your librarian if you struggle with this. Once you are logged in, you can access many articles electronically (and also MathSciNet, but that's not what you asked about).

2. Use a VPN. This will make it appear to the University of Chicago servers that you are on campus, and you can then access library resources as usual. Instructions on how to do this at UChicago are here.

All that said, I also think you are not violating copyright if you find pdfs of articles from other sources in this situation, even so-called "pirate" sources, because you already have the rights to the articles in question through your affiliation to UChicago.

• Community Wiki? – LSpice Jul 14 at 13:22
• None of these options will work: I have just graduated from the University of Chicago – trognanders Jul 14 at 23:52