How to properly reference a source from Debian/Ubuntu in a SPEC file?

[Richard Shaw]

I'm working on package zipios++ as a dependency for another project.
The sourceforge page seems pretty much defunct and the latest source
download there is version 0.1.5 which is FTBFS.

I have found an updated version and patches from Debian which is
version 0.1.5.9 which builds and works with my project but I can not
find any reference to where that source was obtained.

Thanks,
Richard