Heiko states this (regarding the Kullander discus species classified in 2006):
But there work consisted of some unclaer and overlooked (or misinformed) data and it was revised by
Bleher, Sölting, Salzburger & Meyer, 2007 and is now available. It is a 48-page large publication full of colour photographs, maps and tells the entire history and the updated data (distribution, DNA value, closest relatives, etc., etc.) of the 3 (three) good species, as mentioned here under 2.
What I'm looking for is the name of the publication and if anyone knows if it's available.