Coding theorem and strong converse for quantum channels

We present a new proof of Holevo´s (1973, 1977) coding theorem for transmitting classical information through quantum channels, and its strong converse. The technique is largely inspired by Wolfwitz´s (1964) combinatorial approach using types of sequences. As a byproduct of our approach which is independent of previous ones, both in the coding theorem and the converse, we can give a new proof of Holevo´s information bound