Secret Service's Style

LOL. Sounds like someone is clinging to their old college edition. I still go back to my Prentice-Hall Handbook for Writers, 8th Edition (1982).
When in doubt... I own a copy of the Harbrace Handbook of English 1st Ed (c) 1941 that has the previous edition listed as the CCC/WPA Handbook of English, John C. Hodges, Ed. Harcourt Brace and World, pub. not only that it's a 1st printing, and I got it long before I worked there... the 'light version' used to be the Warriner's Series....
I still balk at updating my style guides because of the prices. I don't know what the first edition Harbrace is worth, but I'll wager it's a pretty penny.