What is the recognized way to reference accession data (.sra files) from NCBI as a URI?
The nomenclature is no longer being followed as NCBI is moving all the files to S3/Google cloud. pysradb allows you to fetch the metadata and get the URLs for each individual SRR. See examples in this notebook.

You can also download an entire project by doing:

pysradb download -p &lt;SRP&gt;