Since the very first paragraph mentioned that it had been "sent to me at the Chronicle", and the last paragraph gave the author's e-mail address at the SFChronicle, I didn't see any necessity of giving further attribution. I thought it was obvious.

Well, maybe not so obvious to some, like beardedbruce, OtherDave, Bill D, WYSIWYG, brucie, or jacqui.c, for instance.