Where do I find org.opendatakit.common classes?

Hi everyone, I’m currently trying to compile ODK Sensors code base in my
Android Studio project but I’m running into many errors.

One of those is related to the presence, in the original Sensors code, of
many import of external classes that I’m not finding anywhere on the web.

In particular, I am referring to the one of a project which, based on the
package name structure, should be named “common”.

Those classes are, among others, “DatabaseFactory”, “DataTableColumns”,
“ODKDataUtils”, “ODKDatabaseUtils”.

I have crawled the entire GitHub folder structure without success, could
anyone help me out on this?

Thanks in advance,

Marzio