Regular Singular Problems for Hyperbolic Systems and Their Asymptotic Integration

On a wave equation with singular dissipation

“…For this, we will introduce two zones and apply a diagonalisation based technique to extract leading order terms in each of them. For details on the diagonalisation procedure and its use in a related singular context we refer to [5] or [18], and for a broader discussion of the techniques used see [14].…”