Lawrence Keppie: Legions and Veterans: Roman Army Papers 1971-2000, Franz Steiner Verlag, 2000, ISBN 3-515-07744-8; chapter The Origins and Early History of the Second Augustan Legion, pages 123 - 128 (in Google Books (页面存档备份,存于互联网档案馆)). The chapter discusses predecessors of the II Augusta legion and an inscription on the Triumphal Arch of Orange which mentions II Gallica.