The phrase "to publish the source" means making the code or information behind a software or project available to the public. It allows other people to see and use the original code, make changes, and improve upon it. Full definition
With data drawn from publishing sources, these articles break down costs and profits. (johnaugust.com)
Her book is based primarily on published sources, but she grips the main issues. (totalpolitics.com)
These figures may differ from other published sources showing gains / losses in comparison with the seats held at the dissolution of the council in 2012. (en.wikipedia.org)