The significance of Givens’ observation that Oswald was carrying his clipboard became apparent on December 2, 1963, when an employee, Frankie Kaiser, found a clipboard hidden by book cartons in the northwest corner of the sixth floor at the west wall a few feet from where the rifle had been found.[C4-242] This clipboard had been made by Kaiser and had his name on it.[C4-243] Kaiser identified it as the clipboard which Oswald had appropriated from him when Oswald came to work at the Depository.[C4-244] Three invoices on this clipboard, each dated November 22, were for Scott-Foresman books, located on the first and sixth floors.[C4-245] Oswald had not filled any of the three orders.[C4-246] Eyewitness Identification of Assassin Howard L. Brennan was an eyewitness to the shooting. As indicated previously the Commission considered his testimony as probative in reaching the conclusion that the shots came from the sixth floor, southeast corner window of the Depository Building.[C4-247] (See ch. III, pp. 61-68.) Brennan also testified that Lee Harvey Oswald, whom he viewed in a police lineup on the night of the assassination, was the man he saw fire the shots from the sixth-floor window of the Depository Building.[C4-248] When the shots were fired, Brennan was in an excellent position to observe anyone in the window. He was sitting on a concrete wall on the southwest corner of Elm and Houston Streets, looking north at the Depository Building which was directly in front of him.[C4-249] The window was approximately 120 feet away.[C4-250](See Commission Exhibit No. 477, p. 62.) In the 6- to 8-minute period before the motorcade arrived,[C4-251] Brennan saw a man leave and return to the window “a couple of times.”[C4-252] After hearing the first shot, which he thought was a motorcycle backfire, Brennan glanced up at the window. He testified that “this man I saw previously was aiming for his last shot * * * as it appeared to me he was standing up and resting against the left window sill * * *.”[C4-253]