Thanks Jose for creating the libcerf package.
I placed it in copr and it generated packages okay.
https://copr.fedorainfracloud.org/coprs/kiso49j/libcerf/build/810018/

I also attempted a gnuplot 5.2 (without libcerf) that failed because I did not include "emacs" in BuildRequires.

https://copr.fedorainfracloud.org/coprs/kiso49j/gnuplot/build/809304/ 

I will try adding emacs to the BuildRequires when I have more time.

Regards,
Ronaldo