zgbsv(3) on Linux
The text 137b4ebf95e2, as Debian 4.0 (Etch), Debian 3.1 (Sarge) shipped it.
compute the solution to a complex system of linear equations A * X = B, where A is a band matrix of order N with KL subdiagonals and KU superdiagonals, and X and B are N-by-NRHS matrices