angolan portuguese?

so i can get by pretty well in brazilian portuguese, but lately i've been listening to a lot of angolan music and am having a hard time deciphering the lyrics - i've googled around but can't seem to find much in the way of glossaries/grammars/etc. of colloquial angolan portuguese. any ideas? it can be in either english or portuguese (or french or spanish but i doubt that would exist before the other two) and i don't care at this point if i have to pay for it. thanks in advance!