Identifying kernel soruce for 2.4.18-bf2.4

[brownh@hartford-hwp.com (Haines Brown)]

I need to have installed the kernel source in order to compile a
driver, but have difficulty finding the source for 2.4.18-bf2.4. Is
the answer that the "bf2.4" is just an addition, and that the kernel
source for my kernel is actually just 2.4.18?

Haines Brown