Citing an URL using the Waybackmachine (web.archive.org) I would like to quote the following quotation correctly: 


  Information is the oil of the 21st century and analytics is the internal combustion engine.


In other papers I found out that this quote was said by Peter Sondergaard in 2011 and as source a weblink to a Gartner press release is given: http://www.gartner.com/newsroom/id/1824919. This link is no longer available. So I cannot use it to cite the quote.  

But there is the web service "waybackmachine". It's an internet archive, so I can see here the state of the website from 2017, where this article is still available: https://web.archive.org/web/20170612085034/http://www.gartner.com/newsroom/id/1824919

Is it okay then to use the archive link as the source for the quote? I would use it in bibtex in the following way:

@misc{gartner,
  title = {Gartner Says Worldwide Enterprise IT Spending to Reach \$2.7 Trillion in 2012},
  author = {Pettey, Christy},
  howpublished = {\url{https://web.archive.org/web/20170612085034/http://www.gartner.com/newsroom/id/1824919}},
  note = {Accessed: 2020-04-29},
  year = {2011}
}
This should be fine, though editors get the final say. But since the web is volatile, it is pretty hard to cite a current page and hope that it will be there in a few years. The wayback machine was created for just this purpose.

Referencing potentially volatile information is always dangerous, and any such citation should be accompanied by the date the information was accessed, as you have done here. But the wayback machine (internet archive) is a series of snapshots that shouldn't change. 

Even worse than online information disappearing, is that it can be changed outside your control, making information you relied on say quite different things. 



And, for what it's worth, it is a good idea to donate a bit of money to such resources occasionally to help assure that they don't disappear for lack of support.