Know it's a long shot that anyone will have a pdf of this monograph, but if anyone does could you please send it my way. Need it for a project and unfortunately the closest copy to me is a good 10-12 hour drive.
Ploeg, Alex. 1991. "Revision of the South American cichlid genus Crenicichla Heckel, 1840, with description of fifteen new species and consideration on species groups, phylogeny and biogeography (Pisces, Perciformes, Cichlidae).".Univ. Amsterdam, Netherlands. pp. 1-153