Euler case for a general fourth-order differential equation (Q1777735)

The paper deals with the Euler case for the fourth-order differential equation \[ (p_0y'')''+(p_1y')'+\dfrac12\sum\limits_{j=0}^1\Big[\{q_{2-j}y^{(j)}\}^{(j+1)}+ \{q_{2-j}y^{(j+1)}\}^{(j)}\Big]+p_2y=0, \eqno(1) \] where \(p_i(x)\), \(0\leq i\leq2\) and \(q_i(x)\), \(i=0,1\), are defined on \([a,+\infty)\), are not necessarily real-valued, and are all nowhere zero in this interval The author gives general formulae for the asymptotic forms (as \(x\to +\infty\)) of the fundamental solutions of (1).