“…Block Krylov methods were introduced in the 1970s, starting with the block Lanczos algorithm for linear eigenproblems with repeated eigenvalues [16,27,36]. More recently, block Krylov methods have found applications in model order reduction [2,22,23], for the solution of matrix equations [6,19,31,33], matrix function approximation [24,37,38,40], including multisource electromagnetic modeling [13,15,42,43], and solving linear systems with multiple right-hand sides [12,14,18,21,28,41,48]. While the theory of single-vector rational Krylov spaces is well developed [9,10,44,45,46,47], the block case has only been explored to a limited extent [4,24,29].…”