CentOS
yum install gsl-devel
GLS location (library path), CentOS
/usr/bin/gsl-config
/usr/lib64/libgsl.so
/usr/share/aclocal/gsl.m4
°°°
https://centos.pkgs.org/7/centos-x86_64/gsl-devel-1.15-13.el7.x86_64.rpm.html