Do need it? In the diary von Bock detail proceedings for Voronezh. There is boring to read.
But let's talk about Voronezh (!) - Keitel continued. - At the beginning of the operation, Halder and I had doubts about whether the operation to seize this city would be connected by our mobile forces to such an extent that it would prevent us from advancing in the direction of the Don. After rereading the directive issued by the Army High Command, I asked the Führer, who was then about to fly into the army group, to inform you that the seizure of Voronezh was not mandatory for you. However, after discussing this issue in Poltava on July 3, I got the impression that this idea was not expressed enough  clearly and was not fully communicated to the command of the army group. ”
"Nothing like this. My conversation with the Führer about Voronezh ended with the fact that I told him: “As I understand it, I must take Voronezh, if this is not difficult to do, but I don’t have to get involved in heavy and long battles”. The Fuhrer confirmed this with a nod. But then complications began. The liaison officer at the 4th Tank Army radioed the Supreme Command of the land forces that Voronezh could probably be taken only after heavy fighting. Weichs held the opposite opinion, and I agreed with him. While there were discussions on this issue with the High Command of the Ground Forces, on July 6, the tank battalion of the 24th Panzer Division passed through Voronezh almost without a fight, after which we told the High Command of the Ground Forces that it would not be difficult to capture the city ... ”
"The Fuhrer then said for a long time:" We lost 48 hours near Voronezh. " Apparently, he saw this as a serious waste of time. "
“But one should not forget that the whole operation took less time than planned. Several times, including during the meeting with the Führer on July 3, I reminded of the danger of the Russians retreating. Obviously, under the circumstances, I did everything possible to make a turn to the south as quickly as possible. When Halder called General Sodenshtern on July 5 and told him that the Führer was impatient and wondered why the bridgeheads on Silent Pine were not yet captured, I could answer him that these bridgeheads had already been captured. ”
I did not go into further details, which could illustrate how the army group developed an offensive in a southerly direction, overcoming the resistance of the enemy. I, moreover, did not begin to say that  it was an army group, and not the Supreme Command of the ground forces at all came to the idea of the greater expediency of an attack by the forces of the right wing of the 4th army, as well as managing the entire operation from a single center from the start.
Toward the end, Keitel remarked that the Führer had expressed doubts as to whether he would allow my health to bring the current operation to the end (!), But this statement of the Führer cannot, of course, be taken seriously.
When the conversation ended, Keitel said:
“I'm not sure that I will be able to find an opportunity to tell the Führer in detail all of the above. This is easier to do in a semi-official setting, but the Fuhrer always meets with me in the presence of two stenographers, in whom I cannot discuss such delicate issues! ”