Origen.
An Exhortation to martyrdom ; Prayer ; First principles: book IV : Prologue to the Commentary on the Song of Songs ; Homily XXVII on Numbers /
Origen ; translation and introduction by Rowan A. Greer ; preface by Hans Urs von Balthasar 
. - New York : Ramsay : Toronto : Paulist Press,  1979 
. - xvi, 293  p.  23 cm. 
 - Classics of western spirituality .
<br/><label>  ISBN: </label>0-8091-2198-0