Try 37 CFR 202.1(a)

The following are examples of works not subject to copyright and applications for registration of such works cannot be entertained:

(a) Words and short phrases such as names, titles, and slogans; familiar symbols or designs; mere variations of typographic ornamentation, lettering or coloring; mere listing of ingredients or contents;

Thank you, Father Steve. Your scholarship is impressive.

But lawyers have a way around everything.

Note that the same exclusion for "titles" also applies to "slogans" and the world is awash in proprietary slogans which corporations defend oft-times with unseemly zeal.

The latest example is Starbucks' ill-fated foray against "HaidaBucks" which flamed out (quite literally) in the court of public opinion, not in a court of law.
http://www.haidabuckscafe.com

McDonald's, on the other hand, reigns unchallenged over anything beginning with "Mc", and Budweiser squashed "This spud's for you", a pillow designed for 'couch potatoes'.

Likewise, Johnny Carson prevailed over "Here's Johnny", a supplier of portable 'johns'.

Those who invest money in promoting their wares claim trade-mark protection, rather than copyright protection.

One does not have to register a trade-mark to secure this protection, but it is certainly an intelligent thing to do.

If recollection serves, Johnny Carson did not have a registered trade-mark for "Here's Johnny", yet he succeeded in expunging "Here's Johnny" because of its unflattering association with human excrement. [I was always a fan of Johnny, so I believe his umbrage was righteous.]

If one can make a case that the title of a book is an original coinage associated in the public mind with a particular enterprise of commercial value, for example, "Dianetics", then one can scatter literary clowder (aka "copy-cats") to the wind.

Of course, in situations like this, might usually makes right.

But none of this detracts from the quality of your scholarship, Father Steve, only your certitude.

One can have absolute faith in the Word of God. But the word of man, that's another thing altogether.