Bibliographic references should unambiguously identify research documents.
When identifying a baseprint,
a web address (URL) does not suffice as a reference.
Multiple websites can present a baseprint
and no single website is the authoritative source of a baseprint.
Instead of referencing a web address,
baseprints are referenced with an intrinsic identifier,
such as a Software Heritage ID (SWHID)
[@cosmo_referencing_2020] [@dicosmo:hal-01865790].
The identity of a baseprint is determined by the exact digital encoding of the baseprint.
The exact digital encoding is a sequence of bytes
if a baseprint consists of only a single file.
If a baseprint consists of a directory of files,
then the digital encoding can be a *git tree*.
