Complex sentence: He completed his first book accepted for publication in his mid-thirties: a novel, "The Cry of the Wolf", published by Andersen Press in 1990, which was highly commended by librarians for the Carnegie Medal, which Gillian Cross won for "Wolf".
Split into simpler sentences: He completed his first book accepted for publication in his mid-thirties: a novel, "The Cry of the Wolf", published by Andersen Press in 1990. It was highly commended by the librarians for the Carnegie Medal, which Gillian Cross won for "Wolf".