Ju 88 C-2 and C-4 diference?

[Eduardo]

Hi,

I would like to know the exact diference of these two types?
Some autors stated that the C-2 had "A-1" type wings with Jumo 211 B-1
engines and the C-4 had Jumo 211 G with "A-5" wings.Some others said
that it carries Jumo 211 F
In Michael Balss book about NJG Material losses it cleared identifies a C-2
subtype that had crash landed in Med area with a "A-5" type wing "Photo " with inset ailerons but were reported as a C-2 !!!

Eduardo.