65 out of the top 100 most-cited scientific papers are behind a paywall, with a weighted average cost of $32.33/each BoingBoing Nov 2017
It mentions that some papers are now available from a depository in Russia - SciHub
Unfortunately more than half of the Vitamin D paper found are behind paywalls.
If the paywalled abstract has some new, useful information VitaminDWiki will post it.
VitaminDWiki sometimes accesses PDFs behind paywalls thru
We find about 10% of new Vitamin D papers in SciHub after 6 months.
About 3% are on SciHub near to the time of publication
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