That's "the vat" or the Vatican's Library. Which, of course, means you have to be a Roman Catholic to work there.
However, it is open to anyone who can document their qualifications and research needs and win acceptance to use it. And, that would be really cool as this library recently finished a 9 million Euro renovation upgrade and has an archive of historical documents that is among the very best in the world (especially if you somehow also win approval to access the Vatican Secret Archives which contain another 150,000 items).
Of course, the rub is that the Vatican Library is presently engaged in digitising its collection of manuscripts which it intends to make available online and if you just wait until 2018; you'll be able to access the first installment of those from your home where I assume you have perfectly operational coffee maker with a blend to our liking
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