I am hoping to get some advice on the best reference books regarding EK 1&2 and the Ek1 & 2 spange. As I expand my collect I’d like to get some examples of spanges and as always I prefer to have some reference material on hand while i make my purchase decisions.

Maerz has his book on the EK1 is there something similar in quality for the EK2 and spange?

thanks in advance!