Issue #510 Sep 19, 1973 Issue #511 Oct 03, 1973 Issue #512 Oct 17, 1973 Issue #513 Oct 31, 1973 Issue #514 Nov 14, 1973 Issue #515 Nov 28, 1973 Issue #516 Dec 12, 1973 Issue #517 Dec 19, 1973 Issue #518 Jan 03, 1974 Issue #519 Issue #520 Issue #521 Feb 14, 1974 Issue #522 Feb 28, 1974 Issue #523 Mar 14, 1974 Issue #524 Mar 28, 1974 Issue #525 Apr 11, 1974 Issue #526 Apr 25, 1974 Issue #527 May 09, 1974 Issue #528 May 23, 1974 Issue #529