No, I couldn't. In academia, when publishing a technical paper, only final/published papers count. I doubt that this was a "rule" enforced only at my University or even just in my country. I'd love to hear from others where citing arXiv was at least allowed, but I doubt that that would have been the "standard" way of citing in technical papers.
I must add that this was such a pain for me, as I found several relevant articles on arXiv and I could download and read them. I can't say the same for articles found on Elsevier or ACM, where the relevant articles were mostly in the journals to which my University did not have access...
This strikes me as the wrong way to think about citations.
Citations to a finalized version of a published, peer-reviewed article are "best", both in terms of assigning credit (this is what the authors are supposed to be producing) and as a pointer to more information for the reader (the article has been reviewed[0], it won't change, and there's a stable location for it). Work that isn't peer reviewed shouldn't be outright banned or ignored, but the citation should carry a lot less weight. It hasn't been reviewed, it's subject to change, etc. Since these are essentially someone's musings on a topic, when you cite paper to "prove something" (e.g., you write "The work of XYZ et al. (2017) shows that <some confound> is not a problem"), people will give it correspondingly less weight.
There is a long tradition, predating arXiv by decades, of citing technical reports or "white papers". These are usually written up like a journal article, but might be difficult to publish (all negative results) or contain more details than a typical journal publication would allow. If there is a "journal" version and a "tech report" version, it would probably be better to cite journal version, but I would be shocked if someone actively objected to including a tech report.
(In some disciples, the white papers are also the only thing available. The World Bank and Federal Reserve, for example, often release white papers containing their own data. They rarely bother to publish them in a journal though).
