[1]
RozhankovskayaM.I. and SyavavkoM.S. 1998. Transformation of formal expansions of solutions of linear differential equations in a parameter into continued <em class="a-plus-plus">RITZ</em&gt;-fractions. Ukrains’kyi Matematychnyi Zhurnal. 50, 5 (May 1998), 679–686.